Our Advisers

Abenaki
Alamy Images Inc/Ellen McKnight; Corbis/Bettmann; Getty Images Inc/Archive Photos, NY Daily News Archive; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives; Shutterstock/Elzbieta Sekowska

Algonquin
Alamy Images Inc/Mary Evans Picture Library, Yvette Cardozo; Corbis/Ben Powless; Nativestock/Marilyn “Angel” Wynn; Newscom/UPI/Heinz Ruckeman; Shutterstock/Marek Stuchly

Apache
Alamy Images Inc/Lebrecht Music & Arts Photo Library, Mary Evans Picture Library, Tom Bean; Library of Congress/Edward S. Curtis; Nativestock/Marilyn “Angel” Wynn; Shutterstock/Martin Novak; Superstock Inc/Pantheon

Arapaho
Getty Images Inc/Denver Post/Cyrus McCrimmon; Library of Congress/Edward S. Curtis; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives; Wikimedia

Arctic Culture Area
Alamy Images Inc/19th era; Getty Images Inc/Universal Images Group; Library of Congress; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives; Shutterstock/M. Cornelius

Blackfeet
Alamy Images Inc/SOTK2011; Corbis/Catherine Karnow; Getty Images Inc/Stock Montage; Library of Congress/Rodman Wanamaker; Nativestock/Marilyn “Angel” Wynn; Shutterstock/Dean Fikar

California Culture Area
Library of Congress/Edward S. Curtis; Nativestock/Marilyn “Angel” Wynn

Chinook
Alamy Images Inc/Douglas Lander; Getty Images Inc/Alex Wong; Library of Congress/Edward S. Curtis; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives

Chumash
Braun Research Library Collection, Autry National Center, Los Angeles; p.618; Glow Images/National Geographic; Nativestock/Marilyn “Angel” Wynn; Shutterstock/Richard J. Ashcroft

Cherokee
Alamy Images Inc/David Lyons, Lebrecht Music & Arts Photo Library; Library of Congress/John T. Bowen; Nativestock/Marilyn “Angel” Wynn; Shutterstock/Borislav Borisov

Cheyenne
Dreamstime/Brian Meyer; Getty Images Inc/Getty Images Entertainment, Roll Call/Tom Williams; Library of Congress/Edward S. Curtis; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives

Chickasaw
Alamy Images Inc/Cliff Keeler; Corbis/Peter Turnley; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives; Oklahoma Historical Society; Photo courtesy of Lisa Jones

Choctaw
Corbis/Buddy Mays; Getty Images Inc/McClatchy-Tribune; Glow Images/National Geographic; Nativestock/Marilyn “Angel” Wynn; Shutterstock/Antonio Abrignani, Igor Sirbu

Coast Miwok
Alamy Images Inc/Zuma Press; Getty Images Inc/Photo Researchers; Library of Congress/Edward S. Curtis; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives; The Granger Collection New York; Shutterstock/Steve Byland

Comanche
Getty Images Inc/F. Lewis/Archive Photos; Library of Congress/William S. Soule; Nativestock/Marilyn “Angel” Wynn; Shutterstock/Jill Lang; Superstock Inc/Buyenlarge

Cree
Alamy Images Inc/Aurora Photos, World History Archive; Glow Images/National Geographic, Newberry Library; Library and Archives of Canada/O.B. Buell/Canadian Intellectual Property Office fonds/C-001873;  Nativestock/Marilyn “Angel” Wynn; Newscom/Handout/Stornoway Diamond Corp; North Wind Picture Archives; Shutterstock/Jody Ann

Creek
Muscogee (Creek) Nation; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives; Shutterstock/llaszio; The Granger Collection, New York

Crow
Alamy Images Inc/Interofoto; Getty Images Inc/Buyenlarge, LCDM Universal History Archive; Library of Congress/Edward S. Curtis; Shutterstock/JoLin; Superstock Inc/Pantheon, Prisma

Great Basin Culture Area
Library of Congress/C.C. Pierce, John K. Hillers; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives; Shutterstock/Wildnerdpix

Great Plains Culture Area
Getty Images Inc/Hulton Archive; Library of Congress/Edward S. Curtis, James A. Miller; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives

Hopi
Alamy Images Inc/JT Vintage, Mireille Vautier; Getty Images Inc/Archive Photos; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives; Shutterstock/06photo

Inuit
Corbis/Charles Dharapak; Getty Images Inc/De Agostini Picture Library, Raul Touzon/National Geographic; Library and Archives of Canada/John Reeves; Library of Congress/Edward S. Curtis; Nativestock/Marilyn “Angel” Wynn; Shutterstock/rook76

Iroquois
Alamy Images Inc/Vespasian; Getty Images Inc/Getty Images Entertainment; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives; Shutterstock/EpicStoeckMedia; Superstock Inc

Lakota (Teton Sioux)
Alamy Images Inc/John Parrot/Stocktrek Images; Getty Images Inc/Ulf Anderson; Library of Congress/Edward S. Curtis, John C.H. Grabill; Nativestock/Marilyn “Angel” Wynn; Superstock Inc/John Warburton Lee

Lenni Lenape (Delaware)
Alamy Images Inc/James Nesterwitz; AP Images/Sue Ogrocki; Corbis/Bettmann; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives; Shutterstock/Ricahrd Williamson

Native Hawaiians
Getty Images Inc/Bill Clark, Universal History Archive; North Wind Picture Archives; Shutterstock/Boykov, cleanfotos, Malgorzata Litkowska, Mark52; Superstock Inc/Hawaiian Legacy Archives/Pacific Stock-Design Pic

Navajo
Getty Images Inc/Archive Photos, Universal Images Group; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives

Nez Perce
Library of Congress/G.M. Holland; Nativestock/Marilyn “Angel” Wynn; Shutterstock/Rosalie Kreulen

Northeast Culture Area
Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives

Northwest Coast Culture Area
Glow Images/All Canada Photos, National Geographic; Library of Congress/Edward S. Curtis, Richard W. Dodson; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives; Superstock Inc/Michael DeFreitas/Robert Harding Picture Library

Ojibwa
AP Images/Jim Mone; Getty Images Inc/Tony Bock, Transcendental Graphics; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives; Shutterstock/David P. Lewis, Joseph Scott Photography; Superstock Inc/Christie’s Images Ltd.; Wikimedia

Osage
Alamy Images Inc/Chronicle, Ivy Close Images; Library of Congress/Drum, O.; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives; Shutterstock/Ross Elliot; Wikimedia

Pawnee
Corbis/David Ball, Jacquelyn Martin; Getty Images Inc/Culture Club, De Agostini Picture Library, William Henry Jackson; Glow Images/Werner Forman Archives; Library of Congress/John Carbutt; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives; Shutterstock/gregor

Pequot
Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives; Photo by Alexis Ann; Shutterstock/BestPhotoPlus

Plateau Culture Area
Library of Congress/Edward S. Curtis, N.A. Forsyth, Sarony, Major & Knapp Lith., William Henry Jackson; Nativestock/Marilyn “Angel” Wynn

Pomo
Glow Images/National Geographic; Library of Congress/Edward S. Curtis; Nativestock/Marilyn “Angel” Wynn; Shutterstock/mikeledray; The Sonoma County Library;

Potawatomi
Dreamstime/Ken Backer; Getty Images Inc/Universal Images Group/Hulton Fine Art; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives; Shutterstock/Kevin Key; Wikimedia/National Archives

Powhatan
Alamy Images Inc/Jospeh Sohm, Lebrecht Music & Arts Photo Library; Library of Congress/Richard Norris Brooke; National Parks Service/Colonial National Historical Park; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives; Shutterstock/Studiotouch

Pueblo
Denver Public Library; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives; Shutterstock/fotosutra.com, Sumikophoto; Superstock Inc/Christie’s Images Ltd.

Seminole
Florida State Archives; Getty Images Inc/Archive Photos, Buyenlarge, Hulton Archive; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives; Shutterstock/Joop Hoek

Shawnee
Alamy Images Inc/YvetteCardozo; Library of Congress/Kurz & Allison; Nativestock/Marilyn “Angel” Wynn; Shutterstock/Leena Robinson

Shoshone
Alamy Images Inc/nsf; Library of Congress/Rose & Hopkins; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives; Superstock Inc /Christie’s Images Ltd.

Sioux
Alamy Images Inc/Michael Matthews/Police Images, WorldPhotos; Getty Images Inc/Archive Photos, Dea Picture Library, Universal Images Group; Library of Congress/Edward S. Curtis; Photo courtesy of Virginia Hawk Sneve; Shutterstock/Sekar B; Superstock Inc/Christie’s Images Ltd., David David Gallery

Southeast Culture Area
Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives

Southwest Culture Area
Glow Images/National Geographic; Library of Congress/Pennington & Rowland; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives

Subarctic Culture Area
Corbis/Christopher J. Morris; Library of Congress; North Wind Picture Archives; Science Source/Gary Hincks; Shutterstock/Pi-Lens; Superstock Inc/Images Asset Management Ltd.

Tlingit
Alaska State Library Historical Collection; Getty Images Inc/Science & Society Picture Archives; Glow Images/National Geographic; Library of Congress; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives; Shutterstock/Alberto Loyo

Ute
Alamy Images Inc/David R. Frazier; Library of Congress/ Frank S. Balster, John K. Hiller, Rose & Hopkins; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archive; Shutterstock/Johnny Adolphson, Peter Zijlstra

Wampanoag
Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives; Shutterstock/MWaits; Tara Prindle; The Granger Collection, New York

Zuni
Alamy Images Inc/National Geographic Image Collection; Library of Congress/Edward S. Curtis; Nativestock/Marilyn “Angel” Wynn; North Wind Picture Archives; Photo courtesy of Sunshine Studios; Shutterstock/Antonio Abrignani, Jason Patrick Ross,

All Video provided by North Wind Picture Archive

STATE ARTICLES MEDIA CREDITS

Alamy: Danita Delimont/Walter Bibikow, Lyroky, North Wind Picture Archives, PureStock, W.A. Hamilton, ZUMA Press, Inc.

Alaska State Library/Historical Collections

AP Images: Charles Sykes, Charles Tasnadi, Kellog Co.

BigStockPhoto.com: dosecreative

Bridgeman Images: Collection of the New-York Historical Society, USA/Gilbert Stuart (1755-1828), 1805 (oil on canvas), Peale, Charles W. (1741-1827) & Peale, Rembrandt (1778-1860)
Bridgeman Images/The Julia B. Bigelow Fund/Minneapolis Institute of Arts, MN, USA/View of Fort Snelling, c.1850 (oil on canvas), Thomas, Edward K. (1817-1906)

Capstone Library

Corbis: Bettmann, Burstein Collection/Barney Burstein, Courtesy of Glyndebourne Festival Opera; Ira Nowinski, David Muench, Gordon Parks, Historical, Sygma/James Andanson, Tarker

CriaImages.com/Jay Robert Nash Collection

Dreamstime: Americanspirit, Anton Farrugia, Bonita Cheshier, Carrienelson1, Cenk Unver, Chicco7, Dejan Lazarevic, Ewergryn, Georgios Kollidas, Igor Boldyrev, Jack Rogers, Jerry Coli, Joan Egert, Julia Freeman-woolpert, Julie Bush, Justinjohnson555, Ken Cole, Kenny Tong, Marcio Silva, Martin Ellis, Michael Wood, Mikephotos, Milahelp S.r.o. Milahelp S.r.o., Mille19, Painet, Radomír Režný, Reddogs, Robert Byron, Rox_amar, Roy E Farr, Russell Shively, Scott Anderson, Soh Kee Chuan, Thedisneyresort, Twildlife, Valentin Armianu

Elvis Presley Enterprises, Inc.

Getty Images: AFP, PAUL BUCK, Archive Photos/Consolidated News Pictures, Archive Photos/Interim Archives, Archive Photos/Kean Collection, Archive Photos/MPI, Archive Photos/Stock Montage, De Agostini Picture Library/DEA PICTURE LIBRARY, FilmMagic/Lucy Pemoni, Gamma-Rapho/Jean-Erick PASQUIER, Getty Images Entertainment/Bob Berg, Getty Images Entertainment/Jonathan Fickles, Getty Images Entertainment/Vince Bucci, Getty Images Entertainment/Ulf Andersen, Getty Images News/Stringer/Michael Williams, Getty Images Sport/Clive Brunskill, Getty Images Sport/Sports Studio Photos, Hulton Archive, Hulton Fine Art Collection/The British Library/Robana, Interim Archives, Michael Ochs Archives, National Geographic/Stephen Alvarez, Photo Researchers/Bruce Roberts, Photo Researchers/NYPL/Science Source, Photo Researchers/TOM MCHUGH, Photographer's Choice/Lisa J. Goodman, Science Faction/Library of Congress, Stocktrek Images/John Parrot, Stone/John Kuczala, Time & Life Pictuers/James Keyser, Time & Life Pictuers/Paul Conklin, Time & Life Pictures/Terry Smith, Visuals Unlimited, Inc./Jana Jirak, Visuals Unlimited/Ken Lucas

Globe Photo, Inc.: M. Berkley

Glow Images: Heritage Images/Keystone Archives, ImageBROKER RM/H.-D. Falkenstein, Nomad/, Roger Ressmeyer, Science Faction/Superstock, Superstock

Harpers Ferry Center/National Park Service

Idaho Tourism

iStockphoto: bgwalker, duncan1890, GeorgiosArt, HultonArchive, JanelleStreed, JordanListon, lemonadelucy, mychadre77, Pgiam, RiverNorthPhotography, RJHeurung, roc8jas, sebastian-julian, toddmedia, traveler1116, Willowpix

Karipearls.com

Karon Dubke/Capstone Publishers

Library of Congress
Library of Congress/Prints and Photographs Division: Alexander Gardner, Boyd and Braas, Carl Van Vechten, Carol M. Highsmith Archive, Chas. Fenderich & Co., David Bohrer, Edward S. Curtis Collection, Emil P. Spahn, Geo. Prince, George Grantham Bain Collection, H. B. Lindsley, Harris & Ewing, J.E. Miller, K.C., Jesse Harrison Whitehurst, Karl Schumacher, New York World-Telegram and the Sun Newspaper Photograph Collection, New York World-Telegram and the Sun Newspaper Photograph Collection/Ed Ford, New York World-Telegram and the Sun Newspaper Photograph Collection/Orlando Fernandez, Pach Brothers, Pete Souza, Strauss Peyton, Kansas City, Mo., The George F. Landegger Collection of Alabama Photographs in Carol M. Highsmith's America, U.S. News & World Report Magazine Photograph Collection/Thomas J. O'Halloran, U.S. News & World Report Magazine Photograph Collection/Warren K. Leffler, W.H. Gallagher Co., N.Y., Warren K. Leffler, William Charles Thompson, Alhambra, California
Library of Congress/Rare Book and Special Collections Division

Maxime Guinel

Minden Pictures: Martin B Withers, Michael Quinton

Minnesota Historical Society

Missouri Division of Tourism

NASA
NASA: Donald R. Pettit

National Archives & Records Administration

National Geographic Creative

National Park Service: Everglades National Park, Harpers Ferry Center, Yosemite National Park

Nevada-Landmarks/Paul Sebesta

Newscom: AdMedia/Byron Purvis, akg-images, Album/BULL, CLARENCE SINCLAIR, Album/M.G.M., Andre Jenny Stock Connection Worldwide, Angel Wynn Danita Delimont Photography, Arco Images G/picture alliance/Reinhard, H., Cal Sport Media/Chris Szagola, DanitaDelimont.com Danita Delimont Photography/David R. Frazier, DanitaDelimont.com Danita Delimont Photography/Dennis Brack, Denis Alix, Dennis Brack, Dorling Kindersley Universal Images Group, Everett Collection, Everett Collection/CSU Archives, Fred Stein/picture alliance, Icon SMI/John Cordes, Icon SMI/Tony Donaldson, Icon SMI/TSN/Icon SMI 800/TSN, ITAR-TASS, JD3 WENN Photos, Jeff Malet Photography, Jeff Schultz/Jeff Schultz/Design Pics, KRT/PETE SOUZA, KRT/RANDALL HILL, KRT/TONI STROUD, Kyodo/*, MCT/Grace Saenz Dickson, Oronoz/Album, PHOTOlink, Picture History, picture-alliance/dpa/Oliver Berg, R. APPIANI Universal Images Group/DEA, REUTERS/Jim Young, REUTERS/KEVIN LAMARQUE, Splash News/Photopress PR, Tampa Bay Times/St Petersburg Times, USA Today Sports/Joe Camporeale, Walter Bibikow Danita Delimont, ZOJ WENN Photos/JLC

Newscom: ZUMA Press:, Laura Farr, Robin Nelson, Tina Fultz, Brian Cahn, KEYSTONE Pictures USA, Nancy Kaszerman, The Commercial Appeal

NOAA: Florida Fish and Wildlife Conservation Commission

North Wind Picture Archives

Obsessed Photographers Group: Daron W. Krueger

Science Source: Allen Green, Dirk Wiersma, Mark A. Schneider

Shutterstock: 169420007, 2009fotofriends, 3523studio, 360b, 375Ultramag, 6015714281, aastock, Action Sports Photography, Adam Parent, Africa Studio, AHPix, akiyoko, Al Mueller, Alaettin YILDIRIM, Alan C. Heison, Aleksei Verhovski, Aleksey Stemmer, Alexander Maksimov, Alexey Stiop, alisafarov, Allan Wood Photography, Allen Berezovsky, amir bajrich, Anatoly Vlasov, Andrea J Smith, Andreas Juergensmeier, Andreas Koeberl, Andrew F. Kazmierski, Andrew Zarivny, Andrey Bayda, Andrey Kozyntsev, Aneese, Angel DiBilio, Annmarie Young, Anthony Ricci, Antoly Vlasov, Anton Oparin, apiguide, Artem Furman, Arto Hakola, Artush, ArtWell, atanasija1, B Calkins, B. Speckart, bddigitalimages, Becky Sheridan, Ben Keys, Jr., Benjamin Simeneta, Bertl123, Beth Swanson, BGSmith, bikeriderlondon, Bildagentur Zoonar GmbH, bitt24, Blue Vista Design, bluebullet, bluehand, Blulz60, bobbieh76, Bonnie Taylor Barry, Bos11, Boykov, Boykung, Brad Camembert, Brad Whitsitt, Brandon Alms, Brent Hofacker, Bridget Calip, Bruce MacQueen, Bruce Raynor, C_Eng-Wong Photography, Candace Hartley, carrie-nelson, Cartela, Catmando, Chantelle Bosch, Cheryl Ann Quigley, ChinellatoPhoto, Chris Hill, Christian Delbert, Christopher Halloran, Christopher S. Howeth, Cindy Creighton, cinemafestival, ClimberJAK, col, Colin D. Young, Connie Barr, Creativa, cristalvi, Cristi Bastian, Cristina Negoita, CVHB Photography, cvm, Dani Vincek, Daniel Prudek, Dapixstudio, Darren J. Bradley, Darryl Brooks, David Brian Williamson, David Byron Keener, David Spates, Dawn J Benko, Dean Fikar, Dean Pennala, Debby Wong, Dec Hogan, Delmas Lehman, Denis Tabler, Dennis Donohue, dezi, DFree, Diane Garcia, digitaldarrell, dimair, dinozzaver, Dmitry Kalinovsky, dmvphotos, dolphfyn, Domenic Gareri, Don Bendickson, Don Mammoser, Donna Beeler, doomu, Dorti, Doug Lemke, Doug Meek, dustin77a, ekina, Elena Elisseeva, elinorb, Elizabeth Cronin, EpicStockMedia, Eric Broder Van Dyke, Erick Margarita Images, Erni, Ethan Daniels, Everett Collection, eZeePics Studio, farbled, Featureflash, Filip Bjorkman, Filip Fuxa, Firma V, Flashon Studio, Foodio, forestpath, Francey, Frank L Junior, Fredlyfish4, freya-photographer, Frontpage, fstockfoto, Galyna Andrushko, Gary Whitton, gary yim, gary718, Georgios Kollidas, Gerald A. DeBoer, gillmar, GoBOb, Greg Amptman, Greg Kushmerek, Heather Nicaise, Helga Esteb, Henryk Sadura, hjschneider, Holly Kuchera, humbak, Hysteria, IDAK, Images by Dr. Alan Lipkin, Images by Maria, Imfoto, iofoto, IrinaK, isak55, isoga, Israel Pabon, IVY PHOTOS, J. Bicking, J. Schelkle, Jacek Jasinski, Jakez, Jan Lockwood, Jan Miko, Jan-Dirk Hansen, Jason and Bonnie Grower, Jason Maehl, Jason Patrick Ross, Jay Boucher, Jay Ondreicka, Jay Stuhlmiller, jdwfoto, Jeff Banke, Jeff Feverston, Jeffrey M. Frank, Jeffrey T. Kreulen, jennyt, jessicakirsh, Jill Nightingale, Jim Feliciano, Jiri Hera, Jiri Vaclavek, jo Crebbin, Joakim Lloyd Raboff, Jody Ann, Joe Seer, Joel Shawn, John A Davis, John Brueske, John McCormick, John Wollwerth, Johnny Adolphson, JoMo333, Jon Bilous, Jorg Hackemann, Jorge Moro, Joy Stein, joyfuldesigns, JStone, Juan G. Aunion, Juice Team, Julio Embun, JuneJ, kaband, kanusommer, Karen Gentry, Karen Struthers, Karin Hildebrand Lau, Kat Mack, Katherine Welles, Kathleen Struckle, Kazakov Maksim, Ken Wolter, Kenneth Keifer, Kevin H Knuth, Khakimullin Aleksandr, KimPinPhotography, Kletr, Kondor83, Konstantnin, krasky, Krasowit, kshiota, KumikoMurakamiCampos, KWJPHOTOART, kzww, L F File, Larsek, Laura Mountainspring, lauraslens, Leana Robinson, Legacy Images, LehaKoK, Lenka_N, leungchopan, lev radin, LFRabanedo, Lindsay Douglas, Lissandra Melo, ljh images, Lonnie Gorsline, Lori Howard, LorraineHudgins, Lovell, LUCARELLI TEMISTOCLE, luchschen, Lyndsey McCall, Lynn Watson, M. Cornelius, M.Khebra, Madlen, MaIII Themd, Makarova Viktoria, Malgorzata Litkowska, Manamana, Mara Popa, Marc Venema, MarcelClemens, Marcio Jose Bastos Silva, margouillat photo, Maria Komar, Maridav, Mariusz S. Jurgielewicz, Mark Baldwin, MarkVanDykePhotography, Martha Marks, Mary Terriberry, Maryna Pleshkun, Matt Jeppson, Mavar, max voran, MaxyM, Mayabuns, MBoe, Melinda Fawver, Menna, Merkushev Vasiliy, mextrix, Michael C. Gray, Michael Cummings, Michael Richardson, Miriam Doerr, Mitch Johanson, mj007, Mona Makela, Monika Wieland, Moolkum, MP cz, Muskoka Stock Photos, MVPhoto, Nagel Photography, Nancy Bauer, Nancy Gill, NancyS, Natalia Bratslavsky, Natalia Ganelin, Nerthuz, Neveshkin Nikolay, Nick Lundgren, nikitsin.smugmug.com, Nitr, oksana2010, Oleksandr Lysenko, Oleksiy Mark, Oleksiy Naumov, Olga Lyubkina, Oreena, Oregonez, Orhan Cam, outdoorsman, Patricia Chumillas, Patricia Hofmeester, Pattakorn Uttarasak, Paul Orr, pavel89l, Pekka Nikonen, Pete Spiro, Peter Kunasz, Peter Leahy, PeterVrabel, Phent, Philip Lange, Photo Works, Photographee.eu, photowind, Pi-Lens, Pierre Leclerc, pisaphotography, plasid, Potapov Alexander, R_Szatkowski, Raffaella Calzoni, Rainbohm, Rainer Plendl, Randall Stevens, Randy Miramontez, Raymona Pooler, Raymond B. Summers, Rena Schild, Renata Sedmakova, Ricardo Reitmeyer, Richard Cavalleri, Ritu Manoj Jethani, rj lerich, Rob Hainer, robcocquyt, Robert Manley, Ron Blanton, Rosalie Kreulen, Ross Thompson, RRuntsch, RTimages, Rudy Balasko, Rusty Dodson, Ruth Berkowitz, Ruth Peterkin, Ryan M. Bolton, s_bukley, S.Borisov, sakhorn, Sarah Cates, Sarah Jessup, Sari ONeal, schankz, Sean Lema, Sean Pavone, Sementer, Semmick Photo, Serenethos, Sergey Goruppa, SergeyIT, sergioboccardo, SF photo, Shane Gross, Shari Malin, Sharon Day, sherwood, Shulevskyy Volodymyr, smereka, SNEHIT, Sombra, Songquan Deng, Sony Ho, South Bay Lee, spirit of america, StacieStauffSmith Photos, Stacy Funderburke, Stefano Cavoretto, Steve Bower, Steve Byland, steve estvanik, Steve Heap, Steve Oehlenschlager, Steven Frame, steven pease, StevenRussellSmithPhotos, stocklight, StockPhotosLV, Stocksnapper, straga, Stubblefield Photography, Subbotina Anna, Suchan, Sue Smith, T.Dallas, tab62, Tamara Kulikova, Tarasyuk Igor, TaSha1201, teekaygee, Teresa Levite, Teri and Jackie Soares, TFoxFoto, Thomas Barrat, thomas eder, Tim Roberts Photography, Timolina, TinaImages, Tobias Ott, tobkatrina, Todd Klassy, Tom Grundy, Tom Reichner, Tom Roche, Tom Tietz, tome213, TommyBrison, topseller, torm, Tucker James, Tupungato, tusharkoley, Tutti Frutti, TwilightArtPictures, Tyler Boyes, Tyler Hartl, Tyler Olson, V. Belov, Valentyn Volkov, Valentyn Volkov, Vasilius, Vasily Smirnov, Vera Zinkova, Vibe Images, Victoria V. Ratnikova, Virunja, Vitaly Ilyasov, Vlad G, Vlada Z, Vladimir Sazanov, Vladimir Shulenin, Warren Price Photography, Weldon Schloneger, Wendy Farrington, wiktord, Wildnerdpix, Wollertz, Yellowj, Yongcharoen_kittiyaporn, You Touch Pix of EuToch, Yu Lan, Yufeng Wang, Zack Frank, Zamada, Zeljko Radojko, Zigzag Mountain Art, Zuzule

Superstock Inc.:Nomad

The Bridgeman Art Library/© Look and Learn/Private Collection/John Colter, Baraldi, Severino (b.1930)

U.S. Air Force photo

U.S. Fish and Wildlife Service: Duane Raver, Hollingsworth, J & K

U.S. Geological Survey
U.S. Geological Survey/Nonindigenous Aquatic Species Database/USFWS, Nevada Fish & Wildlife Office

United States Department of Agriculture
United States Department of Agriculture: Loren St. John, Lynn Betts

Veronica Wald

Wikimedia: Alex Huck, Anders Lagerås, Ballista, Bjr97543, Bkell, Cory Maylett, Curtis Clark, DaveHood, David Rix Eibonvale, Didier Descouens, Douglas Kaye, Ebustad, Elmer Chickering, ForestWander, François Marchal, Ghedoghedo, Helgi, HomeinSalem, J. Miers, John Phelan, Jyamuca, Matt Lavin, Megan McCarty, National Oceanic and Atmospheric Administration, National Park Service, Roca Ruiz, Senate.gov, SkepticVK, sleepysmile, Smokeybjb, Steven G. Johnson, T9500, Tolyab, USDA Forest Service, USDA Forest ServiceSRS-4552/Erich G. Vallery, USDA-NRCS PLANTS Database/Sheri Hagwood, Wilson44691

Wikipedia: Craig D. Young

Adaptation
Shutterstock: Alena Ozerova, Brian A Jackson, Dmytro Pylypenko, Everett Historical, Kjersti Joergensen, Matt Jeppson, nicolasvoisin44, scubadesign, Shevs, Stuart G. Porter, Wilm Ihlenfeld, zlikovec

Alternative Energy
Shutterstock: Alex Mit, Carlos Munoz, Chones, Constantine Androsoff, Monkey Business Images, N.Minton, Smileus, Stockr, USAart studio, Vizavi

Animal Cells
Shutterstock: Alila Medical Media, Andrii Vodolazhskyi, Designua, Nimedia, photowind, Tefi

Artificial Selection
North Wind Picture Archives; Shutterstock: catwalker, dotv2, Everett Historical, Grandpa, Mikkel Bigandt

Asking Questions and Defining Problems
Shutterstock: bikeriderlondon, Francesco Ferrarini, Georgios Kollidas, Hurst Photo, Pavel Ilyukhin, Photodiem, Uber Images

Atoms
Shutterstock: Awstok, BlueRingMedia, chromatos, Designua, Dragon Images, Everett Historical, Georgy Shafeev, honglouwawa, Roman Sigaev, snapgalleria

Avalanches
Alamy: Leon Werdinger; Getty Images: AFP/Philippe Desmazes; Shutterstock: Andrew Arseev, bikeriderlondon, Designua, Lysogor Roman, My Good Images, X-treme Video

Bacteria
Science Source: Biophoto Associates; Shutterstock: Adam Gregor, BlueRingMedia, chombosan, heromen30, Lightspring, Oleksiy Fedorov, sumroeng chinnapan; Wikimedia

Biodiversity
Shutterstock: Andrey Gudkov, AuntSpray, Esteban De Armas, geertweggen, Kateryna Kon, Lapis2380, Monkey Business Images, Ryan M. Bolton, Sementer, Tanya Rusanova, wavebreakmedia

Black Holes
Library of Congress; NASA: ESA/D. Coe, J. Anderson, and R. van der Marel (Space Telescope Science Institute), ESA/M.J. Jee and H. Ford (Johns Hopkins University), Goddard Space Flight Center, JPL-Caltech, JPL-Caltech/University of Wisconsin; Shutterstock: Alex Pix, Jiri Vratislavsky, Jurik Peter, Paul Fleet

Blizzards
AP Photo: Pueblo Chieftain/Chris McLean; Getty Images: New York Daily News Archive, Library of Congress; Shutterstock: Devali Photos, Dmitri Ma, Irina Igumnova, Narongsak Nagadhana, Peppersmint, photka, TFoxFoto, Vadym Crutyvus

Camouflage
Dreamstime: Aiyoshi, Mgkuijpers; Library of Congress; Shutterstock: Andrey Gudkov, Bildagentur Zoonar GmbH, Brian Lasenby, Daro Sabljak, Ethan Daniels, gabriel12, Jason Mintzer, JD Duff, Mark52, Matt Jeppson, ostill, Ramon Carretero, rodimov, Sergey Uryadnikov, Tony Campbell, true nature, Vladimir Melnikov

Caves
Shutterstock: andreiuc88, aquapix, Doug Meek, eXpose, Ginger Livingston Sanders, Henrik Larsson, Kuttelvaserova Stuchelova, Pakhnyushchy, redswept, Santi Rodriguez, saraporn, THPStock

Cell Division
Shutterstock: Alila Medical Media, Designua, joshya, Lukiyanova Natalia/frenta, olekpieta, photoiconix, Sergey Nivens

Chemical Changes
Shutterstock: Andrea Danti, Designua, mapichai, Niar, photopixel, sakhorn, Scruggelgreen, snapgalleria

Circulatory System
National Geographic Creative: QA International; Shutterstock: Alexander Ermolaev, Alila Medical Media, BlueRingMedia, Cliparea/Custom Media, Crevis, ifong, Nataly Ponomarenko, u3d, udaix

Climate Types
Capstone Press; Shutterstock: Alexander Kuguchin, Darlene Cutshall, Elliotte Rusty Harold, George Cole, icarmen13, Jon Bilous, K_Boonnitrod, Kamira, KPegg, Lucy Baldwin, OlegD, pisaphotography, Pommy.Anyani, roundstripe, Stephane Bidouze, Stock4KVideo, Taiftin, Tropinina Olga, Trountnut, Vilainecrevette

Clouds
Minden Pictures: Jim Brandenburg; Shutterstock: aga7ta, Alex Egorov, Andrea J. Smith, C_Eng-Wong Photography, ducu59us, Elenarts, Justin Hobson, photolinc, Shico, Stefano Garau, Thatchai Wanitchakun, Thon Varirit

Conservation of Energy
Shutterstock: Andrei Nekrassov, Chones, CoraMax, Dolly, Dutourdumonde Photography, Larysa Drobot, Morphart Creation, Neveshkin Nikolay, Skalapendra

Constructing Explanations and Designing Solutions
Shutterstock: Budimir Jevtic, jamesdeanny, mikeledray, Nicku, wavebreakmedia

Deforestation
Shutterstock: Banana Republic Images, bonga1965, Brian Balster, chris kolaczan, Everett Historical, grafxart, guentermanaus, Kameel4u, RTimages, Tuanjai Pratumma

Deserts
Shutterstock: Adwo, Anton Foltin, astudio, Galyna Andrushko, Konrad Mostert, LuminatePhotos by Judith, Maksym Deliyergiyev, mario.bono, Maxim Petrichuk, Nithid, nopporn, ronnybas, totajla, VIA films, Yegor Larin

Digestive System
National Geographic Creative: QA International; Shutterstock: Alila Medical Media, Bogdan Wankowicz, Designua, La Gorda, sciencepics

Droughts
Shutterstock: Bruce C. Murray, Everett Historical, goodluz, Luiz Ferreira, Rich Lonardo, Robert Adrian Hillman, sima, StudioDo

Dwarf Planets
Dreamstime: Mila Gligoric; NASA: ESA/A. Feild (STScI), ESA/A. Parker (Southwest Research Institute), ESA/Adolph Schaller (for STScI), Johns Hopkins University Applied Physics Laboratory/Southwest Research Institute, JPL-Caltech, JPL-Caltech/ESA/ATG Medialab, JPL-Caltech/UCLA/MPS/DLR/IDA; Shutterstock: edobric, Elenarts, Johan Swanepoel; Wikimedia

Earth
NASA: Goddard Space Flight Center, JPL; Shutterstock: Adwo, Aphelleon, Designua, hareluya, Maxim Tupikov, Mopic, Nicku, Peter Hermes Furian, seveniwe, turtix

Earthquakes
Getty Images: Bettmann; Science Source: Gary Hincks; Shutterstock: Cico, Everett Historical, Leremy, MIVP, Naeblys, Semnic, think4photop, Tom Wang

Electricity and Circuits
Shutterstock: Africa Studio, Chones, Colin Stitt, Designua, Everett Historical, Icatnews, kornilov007, Monkey Business Images, Olivier Le Queinec, SergBob, SJ Travel Photo and Video, snapgalleria, SpaceKris, Volodymyr Burdiak

Electromagnetism
Science Source: SPL; Shutterstock: AlexandrBognat, Designua, Everett Historical, Mauro Carli, oneinchpunch, sciencepics, snapgalleria

Elements and the Periodic Table
Shutterstock: chromatos, concept w, julie deshaies, marianstock, Paul Stringer, Peter Hermes Furian, vchal

Endangered Species
Shutterstock: atiger, AuntSpray, Bargotiphotography, CrackerClips Stock Media, dangdumrong, David J. Martin, Heiti Paves, Larry B. King, Orhan Cam, Richard Whitcombe, Richard Whitcombe, SASER, Volodymyr Gionyk, wk1003mike, Yann Hubert

Endocrine System
National Geographic Creative: QA International; Shutterstock: Alila Medical Media, Designua, joshya, S K Chavan, Sebastian Kaulitzki, stockshoppe, Syda Productions

Energy and Forces
Newscom: KRT/Simmons; Shutterstock: bikeriderlondon, Designua, Fouad A. Saad, Innershadows Photography, Joel O’Brien, MrStudio2, NoPainNoGain

Erosion and Weathering
NASA: MODIS Science Team/University of Wisconsin-Madison/Space Science and Engineering Center/Liam Gumley; Shutterstock: bjul, iryna1, Jan Mika, Matthew J. Thomas, Rick Ray, ronnybas, steveball, sumikophoto, ventdusud, Zack Frank

Evolution
Newscom: akg-images, Mint Images/Frans Lanting; Science Source: David Gifford; Shutterstock: Catmando, Nicku, Paul van den Berg, robuart, Ron Rowan Photography, TravelTelly

Excretory System
National Geographic Creative: QA International; Shutterstock: BlueRingMedia, Designua, joshya, Magic mine, MSSA, S K Chavan, snapgalleria, Tefi

Extinction
Shutterstock: Atomazul, AuntSpray, Catmando, Linda Bucklin, Morphart Creation, Nicolas Primola, Ozgur Coskun, Phonlawat_51, Svetlana Foote, Tekweni1

Floods
Dreamstime: Blackkango; FEMA: Jocelyn Augustino; Shutterstock: Armin Rose, David Greitzer, Dean Kerr, Elzbieta Sekowska, fabiodevilla, forestpath, Jerry Horbert, Leonard Zhukovsky, meunierd, Mike Buchheit, Scott Prokop, VaderVideo, Vladimir Melnikov

Food Chains
Shutterstock: Barbo Bergfeldt, bierchen, bikeriderlondon, Claudia Naerdemann, DPS, Family Business, Greg Brave, mario.bono, mchin, NoPainNoGain, Patila, Sergey Uryadnikov

Food Webs
Shutterstock: alinabel, BGSmith, David Dirga, Dennis W. Donohue, DSLR, Inga Nielsen, kzww, Marco Lavagnini, nj1987, old apple, snapgalleria, Sorin Alb, T.M. McCarthy

Forecasting Weather
Shutterstock: Artur Synenko, Dmitri Ma, Images By Kenny, kosmos111, Lavinia Bordea, LittleStocker, M.Stasy, mahey, orbitrob, peresanz, Viktorija Reuta, Vitoriano Junior

Fossils
Shutterstock: alice-photo, mangomonsters, MarcelClemens, Mark Godden, Oleksandr Presniakov, Rob Bayer, Tanaklit Teja, Thanapun, Vladimir Sazonov

Friction
Shutterstock: Africa Studio, Aleksei Lazukov, BlueRingMedia, Designua, Ensuper, freeproduction, Greg Epperson, Joost van Uffelen, Paolo Bona, supergenijalac, Vanessa Nel, Volt Collection, wk1003mike

Gases
Shutterstock: 3Dme Creative Studio, aekikuis, Alila Medical Media, cigdem, concept w, Designua, Fouad A. Saad, Rob Marmion, snapgalleria, Toa55, Vitoriano Junior

Genes, Chromosomes, and DNA
National Geographic Creative: QA International; Shutterstock: Designua, ellepigrafica, joshya, Rawpixel, Sergey Nivens, Webspark

Genetic Mutations
Shutterstock: Africa Studio, Designua, ellepigrafica, joshya, Maxim Maksutov, Razvan Ionut Dragomirescu, Webspark, WGBH Educ. Foundation

Glaciers as a Water Source
Shutterstock: AsiaTravel, Bernhard Staehli, Dmytro Pylypenko, Gaspar Janos, Jenny Leonard, Rick Ray, saraporn, Sergey Didenko, Sergey_Bogomyako, Thomas Lusth, Tranquility–Photos by Tom

Grasslands
Shutterstock: BGSmith, djgis, Elizabeth C. Zurek, Ingrid Curry, Nancy Bauer, pangcom, Pronghorn Productions, Ricardo Reitmeyer, Ruud Morjin Photographer, Sergey Uryadnikov, Tom Reichner

Gravity
NASA; Shutterstock: Bertl123, Corepics VOF, Crystal Eye Studio, Designua, Hurst Photo, IM_photo, MIVP, wickerwood

Greenhouse Gases and Global Warming
Shutterstock: Astakhov Alexander, corbac40, David Carillet, Denis Burdin, honglouwawa, Marina Lohrbach, rawcaptured photography, Spotmatik Ltd., Vitoriano Junior

Group Behavior
Shutterstock: Gregory Johnston, John Michael Evan Potter, Johnny Adolphson, Michael Pettigrew, NorwayStock, Oleg Znamenskiy, Paul Vinten, Paulphin Photography

Heredity
Science Source: Wilson Sutton; Shutterstock: Capreola, ellepigrafica, lotan, Meletios, Monkey Business Images, Ollyy, Victoria Shapiro, Voronin76

Hibernation
Minden Pictures: Ingo Arndt; Shutterstock: Andreas Argirakis, Annaliese Johnson, Bote1973, MarkMirror, Martin Janca, Mike Bauer, saguari, YanLev, zlikovec

Humans and the Atmosphere
Shutterstock: capa55, cigdem, connel, designbydx, Guas, Joyce Vincent, kekartash, studio23, Toa55, Vadim Petrakov

Humans and the Biosphere
Shutterstock: Dutourdumonde Photography, freedomnaruk, Jeffrey B. Banke, Kodda, mariait, Miguel(ito), Photostock10, Rich Carey, Rich Carey, Stock image, studio23, Volt Collection, wavebreakmedia

Humans and the Earth
Shutterstock: anweber, Derinmedia, Dragana Gerasimoski, Huguette Roe, Martin Mecnarowski, Sergey Neupokoev, Signature Message, ssuaphotos, stockfotoart, Take Photo, VanderWolf Images

Humans and the Hydrosphere
Shutterstock: Ahturner, AuntSpray, Inc, Incredible Arctic, John Wollwerth, Maciej Bledowski, Naeblys, photopixel, shutterlk, Tish1, topseller

Hurricanes
Alamy: dieKleinert, Photo Resource Hawaii; Getty Images: CON/Stephan Kogelman, Joe Raedle, New York Public Library; Newscom: EPA/Gary I. Rothstein; Science Source: José Antonio Peñas; Shutterstock: Cathy Kovarik, Cheryl Ann Quigley, Dopolous, Harvepino, Lisa F. Young, Marc Pagani Photography, Mishella

Igneous Rocks
Shutterstock: aleks-p, Artography, component, corbac40, Don Mammoser, Frontpage, Nickolay Stanev, Ocskay Bence, pics721, sandatlas, Trazos sobre Papel, Tyler Boyes

Immune System
National Geographic Creative: QA International; Shutterstock: beeboys, CLUSTERX, JPC-PROD, Kateryna Kon, Lightspring, Rob Marmion, Roberto Piras, Sebastian Kaulitzki, toeytoey

Information Technology
Newscom: Jonathan Hordle; Shutterstock: Everett Historical, goodluz, Gorodenkoff, Milkovasa, Monkey Business Images, ProStockStudio

Inherited Traits
National Geographic Creative: QA International; Shutterstock: Boule, Christopher Elwell, Dmitry Kalinovsky, GeK, Giovanni Cancemi, Jens Goepfert, Maggy Meyer, Paul Reeves Photography, Tracy Whiteside

Invasive Species
Getty Images: Joe Raedle; Newscom: Zuma Press/Mike Rochford; Shutterstock: 1082492116, Artenex, Baurz1973, Beth Swanson, Danny E Hooks, Jeff Caughey, Martchan

Jobs in Earth Science
Shutterstock: Adwo, Andrey Armyagov, John A. Davis, Microgen, Minerva Studio, REC Stock Footage, rickephotos, Sergio Ponomarev, Wead

Jobs in Life Science
Shutterstock: Abd. Halim Hadi, belizar, dualstock, Kirsanov Valeriy Vladimirovich, pirita, pixelrain, Sergio Ponomarev, stefanolunardi, wavebreakmedia

Jobs in Physical Science
Shutterstock: antb, Dmitry Kalinovsky, lightpoet, lightpoet, PhotoSky, RGtimeline, SF photo

Jupiter
Dreamstime: Radist; NASA: ESA/G. Bacon and M. Estacion (STScI), ESA/I. de Pater and M. Wong (University of California, Berkeley), Hubble Space Telescope Comet Team, JPL, JPL/University of Arizona, JPL-Caltech, JPL-Caltech/SETI Institute, Ken Hodges; Shutterstock: Everett Art, Kirschner, ldambies, MarcelClemens, Mevan, Mopic, mr.Timmi, Tristan3D

Lakes as a Water Source
Shutterstock: Anton Balazh, Elena Elisseeva, Ethan Daniels, Evgeny Sayfutdinov, JeniFoto, John Wollwerth, Nelu Goia, Nickolay Vinokurov, Pierre Leclerc, stockvideofactory, Vereshchagin Dmitry

Layers of the Atmosphere
Science Source; Shutterstock: Bildagentur Zoonar GmbH, Boris Rabtsevich, Crystal-K, Datskevich Aleh, Designua, Fouad A. Saad, IM_photo, Incredible Arctic, Juhku, Mette Fairgrieve, NoPainNoGain, REC Stock Footage

Learned Traits
Dreamstime: Pslow68; Shutterstock: Claudia Otte, JoLin, Kellymmiller73, LeniKovaleva, Mackland, Maggy Meyer, Oleg Podzorov

Life Cycles
Shutterstock: aekikuis, Catchlight Studio, Doug Lemke, jps, kerstiny, KPG-Payless, Matteo photos, Rashid Valitov, Rick Ray, snapgalleria, Vishnevskiy Vasily

Light Energy
Shutterstock: Anton Petrus, Baldas1950, Designua, eveleen, James Benet, KPG_Payless, Milagli, Naga Venkatesh Sankar R, photoiconix, Przemyslaw Skibinski, Tefi

Light Waves
Science Source: SPL; Shutterstock: Daniel Schweinert, Emi Cristea, fluidworkshop, jordache, Pete Hermes Furian, photoiconix, snapgalleria

Liquids
Shutterstock: afitz, Alexey V Smirnov, Andrey_Kuzmin, Designua, Dotta 2, Naeblys, Oksana Shufrych, paulaphoto, Shutterstock Prime

Magnetism
Science Source: Cordelia Molloy; Shutterstock: Aleksandr Pobedimskiy, Ezz Mika Elya, Fouad A. Saad, imagedb, koya979, NoPainNoGain, Pat_Hastings, Peter Hermes Furian, Ruslan Grechka, WGBH Educ. Foundation

Mars
Dreamstime: Elvira Kolomiytseva; NASA: Goddard Space Flight Center, GSFC, J. Bell (Cornell U.)/M. Wolff (SSI), James Bell (Cornell Univ.)/Michael Wolff (Space Science Inst.)/The Hubble Heritage Team (STScI/AURA), JPL, JPL/Cornell University, JPL-Caltech/ASU/UA, JPL-Caltech/GSFC/Univ. of Arizona, JPL-Caltech/MSSS, Pat Rawlings, USGS; Shutterstock: Mopic

Measuring and Mapping Weather
Shutterstock: Aleksandr Stepanov, Andrey Armyagov, Barry Blackburn, Dmitri Ma, dvande, Maksym Darakchi, Maksym Darakchi, pixfly, Praisaeng, Rekindle Photo and Video, Robert Adrian Hillman, Vadym Zaitsev

Mercury
ESA; NASA: Johns Hopkins University Applied Physics Laboratory/Carnegie Institution of Washington, JPL; Shutterstock: Allegresse Photography, BasPhoto, mapichai, Mopic

Metamorphic Rocks
Capstone Press; Shutterstock: Ambient Ideas, Artesia Wells, M Andy, Mark Heighes, Mawardi Bahar, Nikitin Victor, Nonnakrit, sandatlas, Sigur, Vladimir Tronin, vvoe

Metamorphosis
Shutterstock: almond, Eric Isselee, Geoffrey Kuchera, Joe Belanger, Kazakova Maryia, kerstiny, kurt_G, Mathisa, Matt Jeppson, Rick Ray, Steven Russell Smith Photos, vblinov

Migration
Dreamstime: Welshi23; Shutterstock: Ana Gram, BMJ, Dmussman, Ethan Daniels, FotoRequest, Jana Shea, JHVEPhoto, jwjarrett, Keneva Photography, melissaf84, MLArduengo, Olivier Juneau, Paul Sparks, Sjoerd van der Wal, Steve Byland

Mimicry
Shutterstock: Alan Bailey, Arto Hakola, c. mokri austria, JGade, Luke Suen, Matt Jeppson, mountainpix, Suzi44

Minerals
Shutterstock: Adrian Ciurea, Albert Russ, farbled, J. Palys, Julia Reschke, leventina, MarcelClemens, Mclein, MrBright, O.Bellini, Tom Grundy

Molecules and Compounds
Shutterstock: bjul, BlueRingMedia, Designua, Dimitrios Christou, magnetix, qoppi, Ruslan Grechka, schankz, Yuriy Vlasenko

Moon
NASA: Goddard Space Flight Center, JPL-Caltech, NOAA; Newscom: Heritage Images/Fine Art Images; Shutterstock: 3DMaestro, Astrobobo, BlueRingMedia, Dean Pennala, gvictoria, Kuttelvaserova Stuchelova, Matyas Rehak, Melissa King, Thomas Nord

Mountains
Shutterstock: BGSmith, Dennis W. Donohue, Dominik Michalek, Ignacio Salaverria, Robert van der Schoot, Scandphoto, VideoFort, Vitalfoto, Zack Frank

Muscular System
National Geographic Creative: QA International; Shutterstock: Africa Studio, Cliparea/Custom Media, design36, Designua, Helena Ohman, Naeblys, Sebastian Kaulitzki, stihii, Valentyna Chukhlyebova

Natural Resources and the Environment
Shutterstock: Adam Gregor, Delpixel, Dennis van der Water, mitchellsk, Olivier Le Queinec, sciencepics, SpaceKris, stocksolutions, Taina Sohlman, visdia, w.g.design, zhu difeng

Natural Selection
Getty Images: Steve Hansen/The LIFE Images Collection; Science Source: Gary Hincks, Jessica Wilson; Shutterstock: CebotariN, Everett Historical, Evikka, Joseph Scott Photography, Tatiana Shepeleva, Wang LiQuang

Natural Wonders in the Sky
National Geographic Creative: Chris Johns; Shutterstock: Designua, fabiodevilla, Francois Arseneault, Mihai Simonia, Pichugin Dmitry, Shin Okamoto, Traveller Martin, Triff

Natural Wonders in the Water
Alamy: jbdodane; Getty Images: Sean Gallup; Minden Pictures: Norbert Wu; NASA Earth Observatory, Jesse Allen and Robert Simmon; National Geographic Creative: Jason Edwards; Newscom: REX/Phil Rees; Shutterstock: Longjourneys, Natursports, Sapsiwai

Natural Wonders of the Earth
Science Source: Javier Trueba/MSF; Shutterstock: Alvov, alysta, Bill Perry, BL Images, ChameleonsEye, Doug Meek, liseykina, Mariusz S. Jurgielewicz, Richard A. McMillin, ronnybas, Tania Zbrodko, Wollertz

Neptune
iStockphoto: W6; NASA: ESA/G. Bacon and M. Estacion (STScI), JPL, JPL/STScI, JPL/USGS; Shutterstock: iryna1, Mopic, reziart, Tristan3D; Wikimedia: Magnus Manske

Nervous System
National Geographic Creative: QA International; Shutterstock: Alila Medical Media, Blamb, BlueRingMedia, Jacky Co, Jeff Thrower, sciencepics, Sebastian Kaulitzki, Tefi

Newton’s 1st Law
Shutterstock: Allen.G, anekopho, Corepics VOF, Designua, Flystock, Georgios Kollidas, Josfor, Odua Images, VectorLifestylepic, Zurijeta

Newton’s 2nd Law
Shutterstock: Alexey Lysenko, Cilppen, Dario Vuksanovic, Digital Storm, Everett Historical, EvgeniiAnd, foto76, tatuin, Yuriy Rudyy

Newton’s 3rd Law
iStockphoto: Bonnie Caton, Entrieri, Everett Historical, Kucher Serhii, mezzotint, Rich Carey

Nonrenewable Resources
Science Source: Spencer Sutton; Shutterstock: Anatoly Tiplyashin, Andrey N. Bannov, ArturNyk, corlaffra, deadmeat243, iurii, Jaromir Chalabala, JVrublevskaya, Matej Kastelic, Olga Miltsova, zhu difeng

Oceans
Newscom: Splash; Shutterstock: divedog, Eugene Kalenkovich, holbox, kaschibo, lynx_v, Rich Carey, Tracey Winholt

Oceans as a Water Source
Shutterstock: Andrea Izzotti, Atlaspix, Designua, fish1715, Incredible Arctic, jukurae

Organs
Shutterstock: Alila Medical Media, bluezace, Designua, disample_stock, joshya, NoPainNoGain, phil Holmes, Pretty Vectors, snegok13, stockshoppe

Parasites
CDC: Blaine Mathison, Dr. Mae Melvin; Dreamstime: Science Pics; Shutterstock: Cosmin Manci, D. Kucharski K. Kucharska, Gallinago_media, Henrik Larsson, IanRedding, Juan Gaertner, Kateryna Kon, Protasov AN, Sergei Primakov

Photosynthesis
Shutterstock: Designua, Ingrid Prats, Kletr, Kokhanchikov, meunierd, Oxygen, snapgalleria

Physical Changes
Shutterstock: Carlos Andre Santos, Darryl Brooks, Darryl Brooks, Food Lovers, kitty, r.classen, ronnybas, Tatsiana Tsyhanova, Titov Nikolai

Planning and Carrying Out Investigations
iStockphoto: hartcreations; Shutterstock: bikeriderlondon, Dimedrol68, mikeledray, Reece with a C, Sergey Novikov, stockyimages, Uberstock

Plant Cells
Shutterstock: Designua, Dimarion, Dreamy Girl, ellepigrafica, La Gorda, Milena Moiola, wawritto

Pollution
Shutterstock: fish1715, Geoffrey Kuchera, Huguette Roe, Hung Chung Chih, ittipon, Llona Koeleman, M. Shcherbyna, overcrew, Photographee.eu, Rudy Umans, Sam Chadwick, Undersea

Potential and Kinetic Energy
Shutterstock: Arthur Balitskiy, bikeriderlondon, EpicStockMedia, farbled, Fouad A. Saad, Iaroslav Neliubov, James LePage, KPG_Payless, lightpoet, muratart, Oleksandr Kostiuchenko, REC Stock Footage, wawritto

Properties of Matter
Shutterstock: BlueRingMedia, Designua, Im stocker, Joshua Pedersen, My name is boy, Vadim Sadovski

Radio Waves
Shutterstock: DakotaStudios, Designua, Fouad A. Saad, Francois Arseneault, Ivsanmas, Mauro Carli, Nicku

Rain Forests
Shutterstock: Brandon Alms, Dirk Ercken, Eky Studio, guentermanaus, ImagoPhoto, Martin Mecnarowski, Matt Tilghman, Nature Capture Realfoto, nikitsin.smugmug, Ryan M. Bolton, Salparadis, skelos, STILLFX

Reproductive System
Shutterstock: BlueRingMedia, GD Mohamed, Kim Reinick, koya979, Monkey Business Images, saginbay, Sebastian Kaulitzki, wavebreakmedia

Respiratory System
Shutterstock: Alila Medical Media, BlueRingMedia, Cliparea/Custom Media, decade3d–anatomy online, hxdbzxy, sciencepics

Rock Layers and the Rock Cycle
Science Source: Spencer Sutton; Shutterstock: Doug Lemke, farbled, Fotos593, Greene HD Productions Inc, Lindsay Douglas, Matthijs Wetterauw, Mikhail Nekrasov, Milosz_G, MyImages Micha, Steve Estvanik

Saturn
NASA: GSFC/JPL-Caltech, JPL/Space Science Institute, JPL-Caltech, JPL-Caltech/Space Science Institute; Shutterstock: Clara, Elena Korn, MarcelClemens, Mopic, Morphart Creation, photoplotnikov

Savannas
Shutterstock: AndreAnita, Andrzej Kubik, Black Sheep Media, Dudarev Mikhail, Eric Isselee, Flystock, Graeme Shannon, javarman, JaySi, Jo Crebbin, Jorg Hackemann, Natalia Pushchina, Photocreo Michal Bednarek

Sedimentary Rocks
Shutterstock: Aleksandr Pobedimskiy, BarryTuck, Benvalee Onthaworn, Chad Palmer, Eduardo Rivero, Fabio Lamanna, MarcelClemens, Nils Versemann, Robert Adrian Hillman, Snap Happy, sonsam, Wide Lens Films, Yunava1

Skeletal System
Shutterstock: Alexander_P, Blamb, Cliparea/Custom Media, debr22pics, Designua, Kniazeff, La Gorda, NoPainNoGain, Potapov Alexander

Soil
Shutterstock: Denis and Yulia Pogostins, Designua, Elena Arkadova, Everett Historical, Fathur Rahman, Igor Stramyk, Ivan Veselinovic, Ivan Veselinovic, Merkushev Vasiliy, snapgalleria

Solids
Shutterstock: cigdem, hd connelle, Maglara, Maram, Mateusz Fula, phloem, Picsfive, r.classen, Radovan1, Teodora D, Tim UR, Webspark

Sound Energy
Shutterstock: Alila Medical Media, Chris Parypa Photograph, Designua, Fouad A. Saad, Kzenon, Olivier Le Moal, Panaiotidi, Pascal Marchand, solar22, Valentin Valkov

Sound Waves
Shutterstock: Alexander Raths, Alila Medical Media, Black_Diamond, chromatos, Denis Trofimov, Fouad A. Saad, Katerina_S

Space Exploration
NASA: ESA, Goddard Space Flight Center, JPL-Caltech/University of Arizona, JPL-Caltech/University of Wisconsin; Shutterstock: AuntSpray, edobric, Elenarts, Vadim Sadovski, Viacheslav Lopatin; Wikimedia: NASA

Stars and Constellations
iStockphoto: sololos; NASA: ESA/G. Bacon (STScI), ESA/JPL-Caltech; Shutterstock: Dragan Milovanovic, igordabari, MichaelTaylor, sciencepics, shooarts, Traveller Martin, Triff, Yganko, Yoshihiro Miyagi

Streams and Rivers as a Water Source
Shutterstock; 4045, ED Reardon, Frontpage, Galyna Andrushko, Iain Frazer, Igor Jandric, Igor Jandric, Martina I. Meyer, Mikhail Kolesnikov, Miks Mihails Ignats, Rosomak, Sky Light Pictures, Skyward Kick Productions, zlikovec

Taiga
Shutterstock: ArCaLu, Bong, Grigoriy Pil, K19J2, Leonid Ikan, Maksimilian, Nikitin Victor, Secher, Sergei Drozd, TTphoto, YouraPechkin

Tectonic Plates
Capstone Press; Science Source: Planetary Visions Ltd.; Shutterstock: Amy Nichole Harris, Andrea Danti, AuntSpray, Berzina, Designua, K.Narloch-Liberra, Mopic, robin2

Temperate Forests
Shutterstock: Aleksander Bolbot, Ales Liska, Bruce MacQueen, Csehak Szabolcs, Florin Mihai, Matthew Dixon, Stephane Bidouze, Zack Frank

The Milky Way and Other Galaxies
NASA: ESA/The Hubble Heritage (STScI/AURA)/Hubble Collaboration, ESA/The Hubble Heritage Team (STScI/AURA), ESA/Z. Levay and R. van der Marel (STScI)/A. Mellinger, Goddard Space Flight Center, JPL-Caltech, NOAO/ESA/The Hubble Heritage Team (STScI/AURA); Shutterstock: Albert Barr, Alex Mit, Anastasios71, John A. Davis, Yury Dmitrienko

The Senses
National Geographic Creative: QA International; Shutterstock: Alila Medical Media, Crisan Rosu, Designua, Dmitry Naumov, LaKirr, Peter Hermes Furian, rendix_alextian, snapgalleria, stockshoppe

The Sun
NASA; NASA/Scientific Visualization Studio; Newscom: Kyodo; Shutterstock: Aaron Rutten, Andrey Armyagov, Astrobobo, Danshutter, Ivannn, John T. Takai, Linda Brotkorb, Mahesh Patil, Triff; SOHO (ESA & NASA)

The Water Cycle
National Geographic Creative: QA International; Shutterstock: aekikuis, bikeriderlondon, BW Folsom, Designua, Dreamy Girl, Nina B, topseller, TTphoto, wawritto

Thermal Energy
Shutterstock: Burben, Deyan Georgiev, Evgeny Atamanenko, Ezume Images, Fouad A. Saad, magnetix, Narongsak Nagadhana, Triff

Tissues
National Geographic Creative: QA International; Shutterstock: Alila Medical Media, Blamb, Designua, Dimarion, Juan Gaertner, Meoita, paulaphoto, sciencepics

Tornadoes
Newscom: Cultura/Jason Persoff Stormdoctor; Science Source: Jim Reed; Shutterstock: deepspacedave, Designua, Melanie Metz, Minerva Studio, MIVP, okili77, pzAxe, Sari ONeal, Steven Bourelle

Tsunamis
Alamy: Universal Images Group North America; Getty Images: Marco Garcia; National Geographic Creative: QA International; Newscom: REX/Cameron Laird; Science Source; Shutterstock: Andrea Danti, ChameleonsEye, Christian Vinces, Designua, Just_One_Pic

Tundras
Shutterstock: Adwo, Alex Polo, AndreAnita, Andreas Altenburger, Maksimilian, outdoorsman, Sergey Uryadnikov, Sever180, Tony Campbell, Vladimir Melnik

Uranus
NASA: JPL, JPL/STScI, JPL/USGS, JPL-Caltech, Lawrence Sromovsky, University of Wisconsin-Madison/W.W. Keck Observatory; Shutterstock: Area 6, Everett Art, Georgios Kollidas, Joe Belanger, Mopic, photoplotnikov; Wikimedia: NASA

Venus
ESA; NASA: JPL, JPL-Caltech/ESA, Scientific Visualization Studio; Shutterstock: bart acke, Diego Barucco, Georgios Kollidas, Gordon Galbraith, janez volmajer, LeniKovaleva, MarcelClemens, Mopic, Morphart Creation, Tom Hirtreiter

Viruses
Shutterstock: bissig, Blamb, Christos Georghiou, decade3d–anatomy online, jaddingt, MichaelTaylor, Sebastian Kaulitzki, Yuganov Konstantin

Volcanic Eruptions
Capstone Press; Newscom: World History Archive; Shutterstock: Aleksandar Todorovic, Ami Parikh, Azuzl, Dan Lee, Designua, Dr. Morley Read, Elena Kalistratova, Lee Prince, Pfeiffer, Photovolcanica, sandatlas, Serjio74, S-F, silky, Steve Bower, Vacclav, Webspark

Waves and Their Properties
Shutterstock: Chris Van Lennep Photo, Designua, Fouad A. Saad, Matthew Bartolacci, photoiconix

Weather Patterns
National Geographic Creative: QA International; Shutterstock: Designua, Jakinnboaz, Perfect Lazybones, Shelli Jensen, shooarts, Vibrant Image Studio

Wetlands
Shutterstock: Alita Bobrov, Cummings Entertainment, daizuoxin, Dennis W. Donohue, r.classen, Shackleford-Photography, slowfish, thiraphonthongaram

What Are Forces and Motion?
iStockphoto: Jason Lugo; Shutterstock: bikeriderlondon, BlueRingMedia, Carlos Amarillo, dslaven, Everything, imaged, Kai Mortensen, Keith Publicover, Piccia Neri, Pressmaster, supot phanna, wavebreakmedia

What Is Energy?
Shutterstock: banderlog, gyn9037, Jarous, Monika Gniot, Nadia Cruzova, richard finch, Ruslan Grechka, SpaceKris, Vladimir Nenezic

What Is the Biosphere?
National Geographic Creative: QA International; Shutterstock: Abd. Halim Hadi, Designua, MichaelTaylor3d, NoPainNoGain, Vilainecrevette

What Is the Geosphere?
Science Source: Spencer Sutton; Shutterstock: 3dViz, edobric, John T Takai, Niyazz, XYZ

What Is the Hydrosphere?
Shutterstock: Active Stock, Denis Burdin, Jo Crebbin, Josef Hanus, Kazakova Maryia, Kichigin, snowway, Willyam Bradberry

X-Rays
NASA: CXC/Univ. of Toulouse/M.Bachetti et al; Shutterstock: CWA Studios, Designua, dualstock, Everett Historical, itsmejust, jannoon028, Khafizov Ivan Harisovich, konmesa, Tyler Olson

Bullying
iStockphoto: FatCamera, jamesdeanny sturti; Shutterstock: Lopolo, Monkey Business Images, O Driscoll Imaging, Speedkingz

Community Organizations
iStockphoto/andresr; Shutterstock: Helen Fields Hotelfoxtrot, Jenn Huls, Mila Supinskaya Glashchenko, Monkey Business Images, Peter Titmuss, Rawpixel.com, sirtravelalot, SpeedKingz, Suzanne Tucker

Family Types
Shutterstock: Africa Studio, Andy Dean Photography, Annette Shaff, In The Light Photography, Monkey Business Images, nd3000, szefei

Recycling and the Environment
Shutterstock: Coltty, connel, Evan Lorne, Fedorov Oleksiy, Hugette Roe, leungchopan, mangostock, Ralf Broskvar, sirtravelalot, Syda Productions, Ungnoi Lookjeab

Social Norms and Taboos
iStockphoto/simonkr; Shutterstock: Alena Ozerova, Freedom_Studio, FS Stock, Ivan Sujan, Kamil Macniak, Monkey Business Images, Orange Line Media, Peter Bemik, Stephen Coburn, txking

Volunteering
iStockphoto: asiseeit, fstop123, Shutterstock: ESB Professional, Helen Fields Hotelfoxtrot, JohnnyHabell, oliveromg, Rawpixel.com

Being Ethical
iStockphoto: Fertnig, GoodLifeStudio; Newscom/Dylan Martinez/Reuters; Shutterstock: Cynthia Farmer, Everett Historical, IZF, MidoSemsem, racorn, Rekindle Photos and Video, wavebreakmedia

Creating Personal Goals
Getty Images/Brian Bahr/Stringer; iStockphoto: asiseelt, Highwaystarz-Photography, ViktorCap; Shutterstock: a katz, Jacek Chabraszewski, Joana Lopes, sebra

Forming an Identity
iStockphoto/FatCamera; Shutterstock: Andrii Oleksiienko, Dmytro Vietrov, Monkey Business Images, Rawpixel.com

Making Decisions
Alamy/Jay Bray; iStockphoto/andresr; Shutterstock: Hung Chung Chih, Iakov Filimonov, KinoMasterskaya, michaeljung, Sergey Novikov, wavebreakmedia

Solving Problems
Getty Images/Cris Bouroncle; iStockphoto/asiseelt; Shutterstock: arka38, Everett Historical, knet, Meg Wallace Photography, Pyty, Syda Productions

Understanding Facts and Opinions
Alamy/Graham Prentice; iStockphoto/Yuri_arcurs; Newscom/Shamil Zhumatov/Reuters; Shutterstock: DW labs Incorporated, George Rudy, Georgios Kollidas, motion.pl, Pressmaster, Sylvia sooyoN

ADHD
Getty Images/ITN (video); Science Source; Shutterstock: Andrey_Popov, imtmphoto, Monika Wisniewska, Photographee.eu, Pixelbliss, Suzanne Tucker, tomertu, tomom pukesom

Alzheimer’s Disease
Shutterstock: Alexander Raths, Availablelight, bestjeroen, Diego Cervo, Fresnel, Lighthunter, mickyso, Photographee.eu, sfam_photo, Tashatuvango

Autism
iStockphoto: KatarzynaBialaslewicz, Linda Epstein; Science Source: Amelie Benoit Khakurei, Burger/Phanie, Nancy J. Pierce; Shutterstock: 18percentgrey, Roman Yanushevsky, Stock Market Films, Tatyana Dzemileva

Blindness
iStockphoto/chameleonseye; Science Source: Amelie Benoit Khakurei, Spence Grant; Shutterstock: Alliance, Arciom Lobach, goodluz, Tefi, Tinonina, wavebreakmedia

Cerebral Palsy
Getty Images/ITN (vdeo); Science Source/Disability Images; Shutterstock: anyaivanova, belushi, Jaren Jai Wicklund, Lisa F. Young, Olesia Bikei, Pavel L. Photo and Video, sweetmonster

Cystic Fibrosis
Alamy/dpa picture alliance; Getty Images/ITN (video); iStockphoto/KatarzynaBialaslewicz; Science Source/Monica Schroeder; Shutterstock: Alila Medical Media, Amy Myers, hxdbzxy, Konstantin Kolosov

Deafness
Science Source: Disability Images (video), Veronique Burger; Shutterstock: Capifrutta, dwphotos, Elsa Hoffman, Image Point Fr, Monika Wisniewska, Oleksandr Rybitskiy, pablofdezr

Down Syndrome
Shutterstock: Alila Medical Media, Denis Kuvaev, DGLimages, ESB Professional, Joseph Sohm, karelnoppe, Kopytin Georgy, marcel Jancovic, Monkey Business Images

Dwarfism
Alamy: Archive Pics, Rick Wilking/Reuters, Scott Audette/Reuters; Getty Images: Baltimore Sun, David Mepham-WI (video); Shutterstock: Nolte Lourens, pixelaway, science photo, Tinseltown

Dyslexia
iStockphoto/cloudburst79; Science Source: Science Source, Veronique Burger; Shutterstock: adriaticfoto, Ideya, Image Point Fr, James Sedgemore, Levranii, Monkey Business Images, Syda Productions

Epilepsy
iStockphoto: KatarzynaBialaslewicz, patrickheagney, Pixel_away; Science Source: Alfred Pasieka, BSIP, Dr P. Marazzi, Scott Camazine; Shutterstock: Collin Quinn Lormax, motion.pl

Muscular Dystrophy
Getty Images: Chicago Tribune, Denise Truscello; iStockphoto: nico_65, simonkr; Photo courtesy of Curt Buhl; Science Source: Cecilia Magill, Disability Images, Jean-Paul Chassenet; Shutterstock/Alila Medical Media

Art and Music
Alamy: Madeleine Ratz, National Geographic Creative; Getty Images/Barcroft; Shutterstock: Africa Studio, AQ_taro_neo, Corinna Huter, dmitry_islentev, George Dolgikh, Izian Somai, Marisa Estivill, Markord, Monstar Studio, Pyty, Vladimir Wrangel, wideweb

Clothing
iStockphoto: Bartosz Hadyniak, gorodenkoff; Newscom: Fine Art Images Heritage Images, Glasshouse Images; North Wind Picture Archives; Shutterstock: Catwalk Photos, Derek Yamashita, GoneWithTheWind, HitManSnr, Korkusung, Leonardo Emiliozzi, Mikhina Tatyana, PRABHAS ROY, Rawpixel.com, THAWIWAT SAE-HENG

Currency
Getty Images/Marc Hoberman; Newscom/akg-images; Shutterstock: Beneda Miroslav, Martin Prague, Maryna Pleshkun, Only Fabrizio, Rick Ray, small1, vinnstock, Vladimir Sazonov, VTT Studio, W. Scott McGill

Education
Alamy/World History Archive; Getty Images: Bettmann, JUNG YEON-JE/Staff, The Lighthouse Film Co, Inc (video), TONY KARMA/Stringer, ullstein bild; North Wind Picture Archives; Shutterstock: Jannis Tobias Werner, jianbing Lee, Monkey Business Images

Family
Alamy: Art Directors & TRIP, Carol Lee, Novarc Images; Getty Images/Wishing Tree Productions (video); iStockphoto/LeoPatrizi; Shutterstock: ESB Professional, Hans Christiansson, michaeljung, Monkey Business Images; SuperStock/Grant Rooney/age footstock

Food
Shutterstock: Ana del Castillo, Anna_Pustynnikova, Brent Hofacker, DarZel, Dereje, Elsa Hoffmann, Giancarlo Liguori, holbox, Kittipojn Pravallatkul, Leon Rafael, norikko, Prostock-studio, Rawpixel.com, rocharibeiro, SMDSS, Tatiana Brainina

Games
Alamy/Steve Skjold; Getty Images: DEA PICTURE LIBRARY, Jean-Paul Aussenard, YOSHIKAZU TSUNO; iStockphoto/Jesper Elgaard; Shutterstock: CaseyMartin, Corepics VOF, Federica Milella, kaisaya, Karen Sruthers, Live Fire Inc, Monkey Business Images, polkadot_photo, Syda Productions, Tinxi, Zai Di

Governments
Getty Images/The Asahi Shimbun; Newscom/HANDOUT/REUTERS; Shutterstock: Balakate, Burlingham, Erika Cross, Everett Historical, khd, Twocoms, W. Scott McGill

Holidays
Getty Images/Mark Wilson; Shutterstock: ailisa, artcphotos, dreamikon, espies, GTS Productions, JOAT, Nathalie Spellers Ufermann, Pressmaster, Raymond Yong, Suriya99, Tom Wang, videohouse

Homes
Getty Images: Andrew Sacks (video), SEA/G.DAGLI ORTI; North Wind Picture Archives; Shutterstock: Aleksandar Todorovic, alexmisu, Atosan, Breadmaker, Dennis W. Donohue, hxdbzxy, Iakov Filimonov, Kekyalyaynen, Luigi Trevisi, Lukasz Janyst, Magdanatka, Pascal RATEAU, Sergii Rudiuk, vaalaa, Verena Matthew

Languages and Writing
Alamy: Ben Molyneux, CBW; iStockphoto/GlobalStock; Shutterstock: adriaticfoto, Claudio Divizia, CREATISTA, Fedor Selivanov, Fee Jemay, Golden, gpointstudio, Kotomiti Okuma, Sophy Ru

Religions and Traditions
Shutterstock: Antonio Gravante, Art Stocker, beer worawut, Brian Kinney, Donna Ellen Coleman, Elenarts, Fedyaeva Maria, feliks, Leila Ablyazova, leolintang, Napalai Studio, Sergii Rudiuk, Toa55, Volkov Mikhail

Transportation
Shutterstock: Agnieszka Skalska, Amos Rafaeli, Christian Lagerek, Dave Turner, Ewais, GROGL, Nickolay Khoroshkov, Olaf Speier, Pavel Nesvadba, riopatuca, Rudmer Zwerver, S-F, Smitry Kalinovsky, TonyV3112, Trong Nguyen, William Perugini

Disease
Shutterstock: 3Dalia, aslysun, decade3d-anatomy online, Everett Historical, Javier Regueiro, MAGNIFIER, Peteri, racorn, Sirirat, Supoj Pongpancharoen, Surapol Usanakul, VGstockstudio

Environment
Alamy: Newzulu, Nigel Hicks, picturesbyrob; Getty Images/Bryan Chan; Shutterstock: Designua, keantian, Longjourneys, Mike Shooter, Ruslan Gusev, Sawat Banyenngam, Sunflowerey, testing, Victor Lauer

Genocide
Shutterstock: Everett Historical, GiuseppeCrimeni, Goran Bogicevic, Northfoto, Sophie Lenoir, Veni Vidi Vici

Human Rights
Getty Images/Broderick/Stringer; Shutterstock: Charles Haire, Foto593, George Allen Penton, karelnoppe, Marco Crupi, Rick Ray, Sadik Gulec, StanislavBeloglazov, structuresxx

Natural Disasters
Getty Images: ANDREW HOLBROOKE, Barcroft Media, Bernard Weil, FREDERIC J. BROWN, JIM WATSON, NurPhoto, Steve Larson; Science Source: Gary Hincks, Images and Volcans, Peter Menzel; Shutterstock: ArtbeatsEXPRESS, Christian.dk, Designua, Harvepino, Minerva Studio, Naeblys, Paco Espinoza

Conflict over Natural Resources
Getty Images/Olivier Polet; iStockphoto/yoh4nn; Newscom: Pictures From History, TUGELA RIDLEY/EPA; Shutterstock: Anthony Berenyi, Danielle Baslderas, DrimaFilm, Everett Historical, iurii, Jordi C, Lee Prince, longtaildog, robertonencini, VideoFort

Poverty
Newscom: John Alevroyiannis/Mirrorpix, Polaris; Shutterstock: ART production, creativemarc, GagliardiImages, Joseph Sohm, Mettus, Monkey Business Images, nomadvideo, oatjo, Richard Cavalleri, rm

Trade
Alamy: Newzulu, Paul Doyle, Richard Wareham Fotografie; iStockphoto: agustavop, andresr; Shutterstock: AYA images, EQRoy, Faraways, Fotokostic, giddyuptimelapse, Joseph Sohm, kosolovskyy, Lisa F. Young, Rainer Plendi, Sailom, Salvador Aznar, StevenK, vinnstock, WindVector

Creating a Budget
Shutterstock: Andrey_Popov, Casper 1774 Studio, Dmitry Kalinovsky, Iryna Tiumentseva, JohnKwan, pikselstock, Rawpixel.com, Ryman, Syda Productions

Earning Money
Glow Images/Hero Images; North Wind Picture Archives; Shutterstock: Andrey_Popov, Jamie Hooper, Josh randall, Richard A. McGuirk, tsyhun, VIA films, wavebreakmedia

Philanthropy
Shutterstock: a katz, Helen Fields Hotelfoxtrot, Joseph Sohm, lembi, Monkey Business Image, Pongsatorn Singnoy, Syda Productions, wavebreakmedia

Saving Money
iStockphoto/vgajic; Shutterstock: Africa Studio, Bart Sadowski, Christina Richards, Corepics VOF, Darko Zelijkovic, designer491, Iarry1235, Kemal Taner, suksom, Trong Nguyen

Spending Money
Shutterstock: Billion Photos, dean bertoncelj, Everett Historical, Ivelin Radkov, MACKAY PHOTOGRAPHY, LLC, Milkovasa, Rawpixel.com, Tyler Olson, Uberstock

Supply and Demand
iStockphoto/zoranm; Shutterstock: 06photo, Andrey Sosr, Dusit, panpote, tcly, Tyler Olson, Yomka

Understanding Credit
Shutterstock: Andrey_Popov, Brian A. Jackson, Burlingham, Casper1774 Studio, goodluz, Jacob Lund, Marcos Mesa Sam Wordley, motion.pl, Olleg, Stokkete

What is a Free Market System?
Getty Images/Print Collector; Shutterstock: 06photo, Alison Hancock, Bankoo, Dan_Jesperson, George Rudy, Martin Good, Monkey Business Images, Tyler Olson

Anthropology
Alamy/National Geographic Creative; Getty Images/Sky News/Film Image Partner (video); Science Source: Pascal Goetgheluck, Peter Menzel; Shutterstock: Celiafoto, CHAINFOTO24, Jacob Lund, Jannarong, Microgen, Sergey Uryadnikov, Steve Bower

Civics and Political Science
Alamy: Marmaduke St. John, Zuma Press; iStockphoto: asiseelt, Iabsas; Shutterstock: claudia veja images, Iakov Filimonov, Jose Gil, Milles Studio, Monkey Business Images, Rick Ray

Communications
Shutterstock: Dmitry Pichugin, michaeljung, Mila Supinskaya Glashchenko, Monkey Business Images, oliveromg, Sasa Prudkov, smolaw, Stock Footage Inc, stockphoto mania

Economics and Finance
Shutterstock: Andrey_Popov, g-stockstudio, Mark Van Scyoc, Multifocus, Natee K. Jinakum, Olivier Le Queinec, Rawpixel.com, Robert Przybysz

Geography
Alamy: Mark Gibson, Steve Morgan; Getty Images/The Washington Post; Shutterstock: Alison Hancock, Arina P Habich, aSuruwataRi, CandyBox Images, Lisa F. Young, Mike Pellinni, nostal6ie, Rawpixel.com, Rick Ray, Toa55

History
Getty Images” Chris Hondros, Frazer Harrison; iStockphoto/chameleonseye; Newscom/ALEX GRIMM/REUTERS; Shutterstock: Agenturfotografin, Gherzak, Monkey Business Images, SkyworksRF, StockLite

Law
Alamy/Enigma; Getty Images: Mark Wilson, Yellow Dog Productions Inc (video); Shutterstock: bikeriderlondon, Everett Historical, everything possible, Galiullin Ruslan, GaudiLab, gwb, jsp, Steven Frame, wavebreakmedia

Psychology
Getty Images/ullstein bild; iStockphoto: FatCamera, KatarzynaBialaslewicz; Science Source/Thierry Berrod, Mona Lisa Production; Shutterstock: CandyBox Images, Magic mine, Olimpik, Photographee.eu, Uber Images, wavebreakmedia

Sociology
iStockphoto/Luka Lajst; Shutterstock: A and N photography, Aizuddin Saad, Alex Brylov, Helen Fields Hotelfoxtrot, Jacob Lund, Monkey Business Images, sirtravelalot

Africa
Shutterstock: Andrzej Kubik, Bill Kret, Dmitry Eagle Orlav, ekler, Elenarts, Fabio Lamanna, Frontpage, Ivoha, Olga Grinblat, Orhan Cam, paulijuppi, Pichugin Dmitry, Shinelu, TravelNerd, tusharkoley, Villiers Steyn

Antarctica
Newscom/akg-images; Shutterstock: Andreea Dragomir, bikeriderlondon, Designua, Dmytro Pylypenko, Elenarts, fivepointsix, Foto Mous, Mariusz Potocki, Sergey Tarasenko; Superstock/Biosphoto

Asia
Shutterstock: Abdreas Hie, anekoho, Anton Jankovoy, chuyuss, Cuiphoto, dibrova, Elenarts, ESB Professional, Katvic, Ondrej Prosicky, Sasapee, Sean Pavone, stephen Rudolph, TripDeeDee Photo, zhuda

Australia
Shutterstock: Alizada Studios, AustraliaCamer, Byelikova Oksana, Chris Watson, Elenarts, gaborbasch, Kanchana Sukhatip, Martin Maun, N Mrtgh, NathanAN, okili77, Peter Hermes Furian, siwawut, zstock

Europe
Shutterstock: A_Lesik, Alexandru Logel, Anna Maksimyuk, Blue Tuna Ltd, blutack, Elenarts, Krzyzak, MarinaDa, pcruciatti, PhotocechCZ, Seqoya, Shaiith, SuranyiMate, Viacheslav Lopatin

North America
Shutterstock: Aleksandar Todorovic, Elenarts, Galyna Andrushko, Hank Shiffman, Jess Kraft, Kamira, MarkVanDykePhotography, Martin M303, NaturesMomentsuk, Pedro Helder Pinheiro, Photo Image, Spotmatik Ltd, View Apart, Vivid Pixels, West Coast Scapes

South America
Shutterstock: Alice Nerr, Elenarts, Fotos593, Gabriel Rojo, IDAK, Maciej Bledowski, marchello74, Marcos Amend, natkom, Paulo Vilela, sunsinger, Tacio Philip Sansonovski, Travel Stock, Vitoriano Junior, vitormarigo

Appalachian Mountains
Shutterstock: alslutsky, Colorapt Media, Dave Allen Photography, Debbie Steinhausser, Designua, ESB Professional, Jon Bilous, Konstantin L, MarkVanDykePhotography, Paul Tessier; Wikimedia/USGS

Grand Canyon
iStockphoto/desertsolitaire; Shutterstock: Aneese, Anton_Ivanov, Greene HD Productions Inc, Jiri Foltyn, Jorg Hackemann, Mike Buchheit, prochasson Frederic, Skreidzeleu, sumikophoto

Great Lakes
Getty Images/UniversalImagesGroup; iStockphoto/estt; Newscom/KINA/Bertus Webbink; Shutterstock: Ivan Cholakov, JJMedia, MariskaVegter, Nagel Photography, Rainer Lesniewski, Roman Babakin, Thomas Barrat, Tom Reichner, Xin Qiu

Great Salt Lake
Alamy/Don Despain; Newscom/J.C. Butter Glasshouse Images; North Wid Picture Archives; Shutterstock: Andrew Zarivny, Boykov, Dennis W Donohue, Johnny Adolphson, Marco Regalia, Napat, Neil Burton, R.L.Hausdorf, Wesley Aston

Mississippi River
Newscom: ERIK S. LESSER/EPA, Satellite and Aerial Images/Universal Images Group; North Wind Picture Archives; Science Source/Byron Jorjorian; Shutterstock: Gerald Marella, kwan tse, Orhan Cam, Photo Image, Rainer Lesniewski, Rick Ray, Tomaz Kunst

Niagara Falls
iStockphoto/Orchidpoet; North Wind Picture Archives; Shutterstock: Chawalit Siwaborwornwattana, CPQ, FotoRequest, Joao Virissimo, jorome, Nick Doronin, Pete Spiro, Skyward Kick Productions

Rio Grande
Alamy/Jim West; North Wind Picture Archives; Shutterstock: Felix Mizioznikov, Hank Shiffman, kojihirano, Kristy Swanson, Linda Moon, Rainer Lesniewski, Robert Saitta, Tamara Stanaland

Rocky Mountains
iStockphoto/bfophoto; North Wind Picture Archives; Science Source/Henning Dalhoff; Shutterstock: ArtBitz, Constantine Androsoff, f11photo, Kris Wiktor, marekuliasz, Nature Art, Ryan DeBerardinis, welcomia

Natural and Human-Made Boundaries
Shutterstock: Alxcrs, Filipe Frazao, Kopteva Marina, Lester Balajadia, pavalena, Rainer Lesniewski, UnknownLatitude Images, Volina, zol studios

Population Concentrations
Alamy/Maxime Dube; North Wind Picture Archives; Shutterstock: Anton Balazh, blvdone, chuyuss, Cris Foto, Denis Saragionvski, Dmitry Kalinovsky, dnaveh, Everything possible, eXpose, Kenneth Sponsler, photo.ua, Robert Hoetink, Simon Dannhauer

Reading Maps
Getty Images/Martin Lisius; Shutterstock: Andrey Armyagov, ekler, Globe Turner, Leremy, Long Quattro, Nomad_soul, NoPainNoGain, Peteri, Pincasso, satoja satuja

State Capitals
Alamy: Catherine Brown, Franck Fotos, RGB Ventures/Superstock, Stillman Rogers; Getty Images: Education Images, Raymond Gehman; iStockphoto/sestevens; Newscom/Andre Jenny Stock Connection Worldwide; Shutterstock: Ace Diamond, aceshot1, Action Sports Photography, Allen.G, Andrw Zarivny, Aneta Waberska, B Calkins, Charles Knowles, EQRoy, Erika J. Mitchell, ESB Professional, Everett Historical, f11photo, Ffooter, Fotoluminate LLC, Guillermo Olaizola, Henryk Sadura, JPL Designs, Ken Wolter, Kushal Bose, Lincoln Rogers, LynnMedia, Mark Skainy, Mindy Bockewitz, Nagel Photography, Nick Fox, Sailbal Ghosh, Sean Pavone, Songquan Deng, StudioOneNine, Sue Smith, Suzanne Tucker, Trong Nguyen

Global Communication
Shutterstock: Bloomicon, Everett Historical, Gunner Pippel, Haywire Media, Monika Wisniewska, Photographee.eu, Rawpixel.com, Spotmatick Ltd

Cameras
Newscom/Oxford Science Archive Heritage Images; Science Source/Jessica Wilson (video); Shutterstock: Aila Images, Andrew Buckin, Darren Baker, Designua, Everett Historical, Harvepino, RTimages, Samrith Na Lumpoon

Cars
Getty Images: Bettmann, Hulton Archive, PhotoQuest, Science and Society Picture Library, Three Lions; Newscom/Hennessey/Splash News; Shutterstock: Action Sports Photography, Elzbieta Sekowska, Everett Historical, LanaElcova, Mino Surkala, Rick Ray, Scharfsinn

Computers
Getty Images/Science and Society Picture Library; Shutterstock: Everett Historical, Patty Chan, Rawpixel.com, sheyno, Timofeev Vladimir, wavebreakmedia, Ye Liew

Medicine
Getty Images/Al Fenn; Science Source; Shutterstock: adike, adriaticfoto, Aleksandar Karanov, Everett Historical, Ezume Images, UGREEN 3S

Printers
Getty Images: Evening Standard, Mirrorpix; Science Source/British Library; Shutterstock: asharkyu, Everett Historical, FabrikaSimf, Fedor Selivanov, Nirat.pix, science photo, WUTTISAK PROMCHOO

Telephones
Getty Images/George Rinhart; Glow Images/Janie Airey; Science Source/Bildagentur-online/Tschanz; Shutterstock: Alila Medical Media, Denys Prykhodov, Everett Historical, guteksk7, LDprod, POM POM, Rick Ray

Internet Publishing
Shutterstock: Africa Studio, Diego Cervo, Georgejmclittle, Jeramey Lende, MaxxiGo, mmkarabella, Monkey Business Images, SpeedKingz, welcomia

Online Safety
Shutterstock: Blend Images, Cefo design, Chinnapong, JMiks, oliveromg, Rawpixel.com, Ronnachai Palas, SpeedKingz, wavebreakmedia

What is the Internet?
Getty Images: MIGUEL RIOPA, Science and Society Picture Library; Shutterstock: beboy, DDCora, Denys Prykhodov, ESB Professional, Georgejmclittle, Has-Joachim Roy, Inara Prusakova, nmedia, Rawpixel.com

Executive Branch
Getty Images: Bloomberg, Buyenlarge, Chip Somedevilla, Hearst Newsreel (video), Mark Wilson, TIBBON/AFP; Shutterstock: Joseph Sohm, Orhan Cam

Judicial Branch
Getty Images: Bettmann, Image Works, Yellow Dog Productions Inc (video); iStockphoto: Image Source, RichLegg; Shutterstock: eurobanks, Sea Pavone, Victor Moussa

Legislative Branch
Alamy/DOD Photo; Getty Images: Drew Angerer, FedNet (video), MCT; Newscom/Staff KRT; Shutterstock: Ferhat, Kamira, Roman Babakin

Understanding Checks and Balances
Getty Images: Alex Wong, FedNet (video), JIM WATSON; Shutterstock: Kristi Blokhin, Andrey_Popov, Angel Soler Gollonet, Joseph Sohm, JPL Designs

Citizen Responsibilities
iStockphoto/josephhgruber; Shutterstock: Africa Studio, bikeriderlondon, Burlingham, Diego G Diaz, Everett Historical, KieferPix, Pamela Au, Photographee.eu, Rick Ray, Syda Productions

Immigration
Getty Images/Historical; Shutterstock: Everett Historical, Marzolino, Rena Schild, Rick Ray

Federal Government
Alamy: Media Punch Inc, Scott J. Ferrell/Congressional Quarterly, Stock Connection Blue, Wiskerke; Getty Images: Alex Wong, JIM WATSON, Onyx Media, Lic-Footage; Newscom/Olivier Douliery/SIPA; Shutterstock: Angel Soler Gollonet, Orhan Cam, Steven Frame

State Government
Alamy/ZUMA Press Inc; Getty Images: Christopher Capozziello/Stringer, Getty Images; Shutterstock: amadeustx, CrackerClips Stock Media, Fotoluminate LLC, Juli Hansen, koya979, RRuntsch, welcomia

Local Government
iStockphoto/Smileus; Shutterstock: Barry Blackburn, Cary Kalscheuer, ChameleonsEye, Dominick Jr, Frank Merfort, ND700, Ocean Image Photography, stock_photo_world, stockelements

Abraham Lincoln
North Wind Picture Archives; Shutterstock: Everett Historical, Rick Ray

Dwight Eisenhower
Getty Images: Library of Congress, PhotoQuest; Newscom: akg-images, Everett Collection, Glasshouse Images, National Archives/MCT, U.S. Army via CNP; Shutterstock/Rick Ray

Franklin Delano Roosevelt
Alamy/Everett Collection Historical; Newscom: akg-images, Everett Collection, Ingram Publishing; Shutterstock/Rick Ray

George Washington
Alamy/Pictorial Press; Getty Images/Smithsonian (video); Newscom: akg-images, Everett Collection; North Wind Picture Archives; Shutterstock: Everett Historical, Everett Historical-Art, Victorian Traditions

John F. Kennedy
Getty Images: Bettmann, Corbis Historical, Historical, Hulton Archive, Keystone/Staff, Stringer; Newscom: CNP/AdMedia, CNP/AdMedia/SIPA, Robert Knudsen/dpa/picture-alliance; Shutterstock/Rick Ray

Theodore Roosevelt
Getty Images/Smith Collection/Gado/Contributor; Newscom: Everett Collection, The Print Collector Heritage Images; Shutterstock: Everett Historical, Rick Ray, Zack Frank

Thomas Jefferson
Newscom: Active Museum/Le Pictorium, Album/Prisma, Glasshouse Images; North Wind Picture Archive; Shutterstock: Chris DeRidder and Hans VandenNieuwendij, Daniel M. Silva, Everett Historical, Jess Kraft, Steve Heap

Ulysses S. Grant
Getty Images: Heritage Images/Contributor, Interim Archives, MPI/Stringer; Shutterstock: Everett Historical, Joe Ravi, John Wollwerth, Rick Ray

Discovering America
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American Colonies
Getty Images: Bettmann, MPI/Stringer, Sky News/Film Image Partner; North Wind Picture Archives; Shutterstock/Everett Historical

Revolutionary War
Newscom: Album/Prisma, Everett Historical; North Wind Picture Archives; Shutterstock: Everett Historical, Storytellers

Westward Expansion
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Civil War
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Industrial Revolution
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The US in World War I
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The US in World War II
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20th Century Social Movements
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Current Events
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Articles of Confederation
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The Bill of Rights
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The 13th Amendment
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The 19th Amendment
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The US Constitution
Getty Images: Bettmann, GraphicArtis; North Wind Picture Archives; Shutterstock: Everett-Art, Everett Historical, Festa, Jack R. Perry Photography, Lana Veshta, Mark R

Declaration of Independence
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Emancipation Proclamation
Alamy/PF-(usna); North Wind Picture Archives; Shutterstock: Everett Historical, Rainer Lesniewski, Rock Ray

Magna Carta
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Virginia Plan
Alamy: Danita Delimont, Glasshouse Images; Newscom/Picture History; North Wind Picture Archives; Shutterstock: Everett Historical, JPL Designs

History of National Celebrations
Alamy/GL Archive; Getty Images/Agence France Presse; Shutterstock: e2dan, Everett Historical, Monkey Business Images, Nadia Leskovskaya, Orhan Cam, redswept, wavebreakmedia

Susan B Anthony
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Clara Barton
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Cesar Chavez
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Benjamin Franklin
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Langston Hughes
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Iroquois Confederacy
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Rosa Parks
Alamy/Everett Collection Inc; Getty Images: Archive Films (video), Bettmann, Don Cravens, The Washington Post, William Philpott; Newscom: Everett Collection, World History Archive

Sacagawea
Bridgeman ImagesLewis and Clark with Sacagawea (colour litho) (detail), Paxson, Edgar Samuel (1852-1915) / Private Collection / Peter Newark American Pictures; Getty Images: Historical, MPI/Stringer, Smithsonian (video); North Wind Picture Archives; Shutterstock: Ace Diamond, Michael Warwick

Understanding Timelines
Getty Images/Bloomberg Video-Footage (video); Science Source/Spencer Sutton; Shutterstock: Anastasios71, Artissara, Kaspars Grinvalds, Rawpixel.com, world of vector

Arlington National Cemetery
Shutterstock: Everett Historical, Frontpage, Jarno Gonzalez Zarraonandia, M DOGAN, Olga Bogatyrenko, Rekindle Photo and Video, Zack Frank

Independence Hall and the Liberty Bell
iStockphoto/f11photo; Library of Congress/Prints and Photographs Division; Shutterstock: Atomazul, Bill Perry, f11photo, Joseph Sohm, Rebekah McBride, Ritu Manoj Jethani

Library of Congress
Getty: Bernard Hoffman/Contributor, MPI/Stringer, Stefan Wiesen (video); Shutterstock: Galina Mikhalishina, Martina Roth, Orhan Cam, photosounds, Tinnapom Sathapornnanont, Tupungato

Lincoln Memorial
Library of Congress/Prints and Photographs Division; Shutterstock: Jonathan Lenz, Melpomene, Orhan Cam, Steve Heap, Valerii lavushenko, Yvonne Navalaney

Mount Rushmore
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State of Liberty
Library of Congress/Prints and Photographs Division; Newscom: akg-images, CARLO ALLEGRI/REUTERS, DAVID GOLDMAN/POOL/EPA; Shutterstock: ChameleonsEye, Helen Fields Hotelfoxtrot, maskalin, Matej Hudovemik, Stanley Ford, Sviluppo, UbjsP

Washington Monument
Getty Images: Richard Baker, Three Lions; Newscom: akg-images, Everett Collection, Nps/ZUMA Press; Shutterstock: iofoto, Melpomene, Orhan Cam, PhotosbyAndy

The White House
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American Flag
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Bald Eagle
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Pledge of Allegiance
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Star-Spangled Banner
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Uncle Sam
Alamy/Cindy Hopkins; Getty Images/Bettmann; Library of Congress/Prints and Photographs Division; Shutterstock: EdenExit, Everett Historical, Marinaccio, stockstudios


PGN Social Studies Quotations

20th Century Social Movements, slide 1: Rutgers. "Declaration of Sentiments and Resolutions." The Elizabeth Cady Stanton & Susan B. Anthony Papers Project. Aug. 2010. 27 July 2017. http://ecssba.rutgers.edu/docs/seneca.html

20th Century Social Movements, slide 6: "Brown v. Board of Education (1954)." Our Documents. 27 July 2017. https://www.ourdocuments.gov/doc.php?flash=false&doc=87

Abraham Lincoln, slide 4:  Peoria Speech, October 16, 1854." National Park Service. 10 April 2015. 27 July 2017. https://www.nps.gov/liho/learn/historyculture/peoriaspeech.htm

Abraham Lincoln, slide 5: "We Must Not Be Enemies." Library of Congress. 27 July 2017. https://www.loc.gov/wiseguide/mar04/enemies.html

Abraham Lincoln, slide 6: Stephen M. Archer. "Booth, John Wilkes." American National Biography Online. Feb. 2000. 27 July 2017. http://www.anb.org/articles/04/04-01210.html

American Flag, slide 2: "The History of the Stars and Stripes." USA.gov. 27 July 2017. https://publications.usa.gov/epublications/ourflag/history1.htm

American Flag, slide 4: "Address on Flag Day June 14, 1917." The American Presidency Project. 27 July 2017. http://www.presidency.ucsb.edu/ws/?pid=65400

Art & Music: Williard E. Misfeldt. "Dalí, Salvador." World Book Advanced. 2 March 2017. http://www.worldbookonline.com/advanced/article?id=ar146940

Bald Eagle: "Presidents Kennedy's Bald Eagle Pledge." John F. Kennedy Presidential Library and Museum. 27 July 2017. https://www.jfklibrary.org/Research/Research-Aids/Ready-Reference/JFK-Fast-Facts/Appeal-Bald-eagle.aspx

Benjamin Franklin: “Benjamin Franklin: The Writer.” America’s Library. 27 July 2017. http://www.americaslibrary.gov/aa/franklinb/aa_franklinb_writer_3.html

Civil War, slide 3: "Sherman's March." History.com. 27 July 2017. www.history.com/topics/american-civil-war/shermans-march

Civil War, slide 4: "Stonewall Jackson." History.com. 27 July 2017. www.history.com/topics/american-civil-war/stonewall-jackson

Civil War, slide 6: "The Gettysburg Address." Abraham Lincoln Online. 27 July 2017. http://www.abrahamlincolnonline.org/lincoln/speeches/gettysburg.htm

Clara Barton: "Clara Barton (The Angel of the Battlefield)." The Ohio State University. 27 July 2017. https://ehistory.osu.edu/biographies/clara-barton-angel-battlefield

Creating Personal Goals: "Michael Jordan Didn't Make Varsity—at First." Newsweek. 17 Oct. 2015. 27 July 2017. http://www.newsweek.com/missing-cut-382954

Current Events: Dallon Christensen. "'Those Who Fail to Learn from History Are Doomed to Repeat It.' Sir Winston Churchill." WhiteBoard. 27 July 2017. http://www.whiteboardbusiness.com/those-who-fail-to-learn-from-history-are-doomed-to-repeat-it-sir-winston-churchill/

Declaration of Independence: "Epitaphs." Library of Congress. 27 July 2017. https://www.loc.gov/teachers/classroommaterials/connections/thomas-jefferson/langarts5.html

Dwight Eisenhower, slide 4: EISENHOWER'S ORDER OF THE DAY UPON THE INVASION OF NORMANDY, JUNE 6, 1944. The National D-Day Memorial. 27 July 2017. https://www.dday.org/history/d-day-the-invasion/the-leadership.html

Dwight Eisenhower, slide 5, quote 1: Jim Newton. Eisenhower: The White House Years. New York: Random House Inc., 2011, p. 206.

Dwight Eisenhower, slide 5, quote 2: Dwight D. Eisenhower Presidential Library, Museum and Boyhood Home. 27 July 2017. https://www.ourdocuments.gov/doc.php?flash=true&doc=90&page=transcript

Emancipation Proclamation: Zach Klitzman. "Black Reaction to the Emancipation Proclamation." President Lincoln's Cottage. 22 Feb. 2013. 27 July 2017. http://www.lincolncottage.org/black-reaction-to-the-emancipation-proclamation/

Federal Government, slide 4: "The Oath of Office." National Museum of American History. 27 July 2017. http://americanhistory.si.edu/presidency/1b2.html

Federal Government, slide 6: "Brown v. Board of Education (1954)." Our Documents. 27 July 2017. https://www.ourdocuments.gov/doc.php?flash=false&doc=87

Franklin Delano Roosevelt, slide 2: Geoffrey C. Ward and Ken Burns. "The Roosevelts: An Intimate History." New York: Alfred A. Knopf, 2014. 27 July 2017. https://books.google.com/books?id=maphBAAAQBAJ&pg=SA1-PA76&lpg=SA1-PA76&dq=I+always+felt+entirely+out+of+things,+fdr&source=bl&ots=eM4y_KqfZs&sig=HLuY4RcaqaZ3rGjECcw3SmAABGA&hl=en&sa=X&ved=0ahUKEwiUv67ql8rSAhUk3YMKHQu2BnEQ6AEIJTAC#v=onepage&q=I%20always%20felt%20entirely%20out%20of%20things%2C%20fdr&f=false

Franklin Delano Roosevelt, slide 4: "Franklin D. Roosevelt 131 - Address Accepting the Presidential Nomination at the Democratic National Convention in Chicago." The American Presidency Project. 27 July 2017. http://www.presidency.ucsb.edu/ws/?pid=75174

Franklin Delano Roosevelt, slide 5: "FDR's First Inaugural Address Declaring 'War' on the Great Depression." National Archives. 27 July 2017. https://www.archives.gov/education/lessons/fdr-inaugural

Franklin Delano Roosevelt, slide 6: "Franklin D. Roosevelt 154 – Fireside Chat." The American Presidency Project. 27 July 2017. http://www.presidency.ucsb.edu/ws/?pid=15917

Franklin Delano Roosevelt, slide 7: "Speech by Franklin D. Roosevelt, New York (Transcript)." Library of Congress. 27 July 2017. https://www.loc.gov/resource/afc1986022.afc1986022_ms2201/?st=text

George Washington, slide 1: "First in War, First in Peace, and First in the Hearts of His Countrymen." George Washington's Mount Vernon. 27 July 2017. http://www.mountvernon.org/digital-encyclopedia/article/first-in-war-first-in-peace-and-first-in-the-hearts-of-his-countrymen/

George Washington, slide 2: "Cherry Tree Myth" George Washington's Mount Vernon. 27 July 2017. http://www.mountvernon.org/digital-encyclopedia/article/cherry-tree-myth/

Grand Canyon: "Grand Canyon." National Park Service. 6 June 2013. 27 July 2017. https://www.nps.gov/grca/learn/news/grand-canyon-national-park-presents-living-history-performance-of-president-theodore-roosevelt.htm

Great Salt Lake: "Utah's Great Salt Lake is Disappearing, According to Study." The Weather Company.10 March 2016. 27 July 2017. https://weather.com/science/environment/news/great-salt-lake-drying-up

Human Rights: "Qatar 2022: 'Forced Labour' at World Cup Stadium." BBC News. 31 March 2016. 27 July 2017. http://www.bbc.com/news/world-middle-east-35931031

Independence Hall and the Liberty Bell, slide 1: "The Liberty Bell." National Park Service. 27 July 2017. https://www.nps.gov/inde/learn/historyculture/stories-libertybell.htm

Independence Hall and the Liberty Bell, slide 2: Ibid.

Independence Hall and the Liberty Bell, slide 4: Ibid.

Independence Hall and the Liberty Bell, slide 6: Richard Dunbar. Philadelphia. Florence, Italy: Casa Editrice Bonechi, p. 10.

Independence Hall and the Liberty Bell, slide 7: "Founding Father." Twin Cities Public Television. 27 July 2017. http://www.pbs.org/benfranklin/l3_citizen_founding.html

Industrial Revolution: "Samuel Slater." PBS. 27 July 2017. http://www.pbs.org/wgbh/theymadeamerica/whomade/slater_hi.html

John F. Kennedy, slide 1: "'Ask Not...': JFK's Words Still Inspire 50 Years Later." NPR. 11 Jan. 2011. 27 July 2017. http://www.npr.org/2011/01/18/133018777/jfks-inaugural-speech-still-inspires-50-years-later

John F. Kennedy, slide 2: "John F. Kennedy Speeches." John F. Kennedy Presidential Library and Museum. 27 July 2017. https://www.jfklibrary.org/Research/Research-Aids/JFK-Speeches/Civil-Rights-Radio-and-Television-Report_19630611.aspx

Law: "Sumer." Ancient History Encyclopedia. 28 April 2011. 27 July 2017. http://www.ancient.eu/sumer/

Library of Congress, slide 1: "History of the Library." Library of Congress. 27 July 2017. https://www.loc.gov/about/history-of-the-library/

Library of Congress, slide 6: "On These Walls Inscriptions and Quotations in the Buildings of the Library of Congress." Library of Congress. 27 July 2017. http://www.loc.gov/loc/walls/madison.html

Lincoln Memorial, slide 4: "90th Anniversary of the Dedication of the Lincoln Memorial." National Park Service. 27 July 2017. https://www.nps.gov/nama/blogs/90th-Anniversary-of-the-Dedication-of-the-Lincoln-Memorial.htm

Lincoln Memorial, slide 6: “Lincoln Memorial Commission.” Lincoln Financial Foundation Collection. 27 July 2017. https://archive.org/details/inthistempleasin00unit

Magna Carta: "Magna Carta story illuminated by discovery of medieval poem." The Guardian. 27 November 2014. 27 July 2017. https://www.theguardian.com/culture/2014/nov/27/magna-carta-runnymede-melrose-chronicle

Mount Rushmore, slide 3: John Taliaferro. "Great White Fathers: The Story of the Obsessive Quest to Create Mount Rushmore." PublicAffairs: New York, 2002, p. 343.

Mount Rushmore, slide 4: "The History Lesson of Mount Rushmore." Step by Step. 27 July 2017. http://www.stepbystep.com/The-History-Lesson-of-Mount-Rushmore-132198/

Mount Rushmore, slide 6: Gutzon Borglum. "Geologic Forces." National Park Service. 27 July 2017. https://www.nps.gov/moru/planyourvisit/upload/geologic_forces2.pdf

Philanthropy: "About Us." Rockefeller Foundation. 27 July 2017. https://www.rockefellerfoundation.org/about-us/

Pledge of Allegiance, slide 1: "The Pledge of Allegiance." U.S. Department of Veterans Affairs. 27 July 2017. https://www.va.gov/opa/publications/celebrate/pledge.pdf

Pledge of Allegiance, slide 2, quote 1: "Under God: The Evolution of the Pledge of Allegiance." HistoryNet. 27 July 2017. http://www.historynet.com/god-evolution-pledge-allegiance.htm

Pledge of Allegiance, slide 2, quote 2:"The Man Who Wrote the Pledge of Allegiance." Smithsonian Magazine. Nov. 2003. 27 July 2017. http://www.smithsonianmag.com/history/the-man-who-wrote-the-pledge-of-allegiance-93907224/

Revolutionary War: "What Was the 'Shot Heard Round the World?'" History.com. 22 Jan. 2015. 27 July 2017. http://www.history.com/news/ask-history/what-was-the-shot-heard-round-the-world

Rosa Parks: "Rosa Parks Arrested." Library of Congress. 27 July 2017. https://www.loc.gov/item/today-in-history/december-01

Sacagawea: James P. Ronda. "Lewis & Clark Among the Indians Appendix: A Note on Sacagawea." University of Nebraska PressLincoln and London. 1984. 27 July 2017. https://lewisandclarkjournals.unl.edu/item/lc.sup.ronda.01.appendix#ln1103

Solving Problems: Richard Langworth. Churchill By Himself. The Definitive Collection of Quotes. New York: PublicAffairs, 2011, p. 525.

Star-Spangled Banner, slide 1: "The U.S. National Anthem." U.S. Army. 27 July 2017. http://www.music.army.mil/music/nationalanthem/

Star-Spangled Banner, slide 2: "Reading 2: Francis Scott Key and the Writing of 'The Star-Spangled Banner.'" National Park Service. 27 July 2017. https://www.nps.gov/nr/twhp/wwwlps/lessons/137fomc/137facts2.htm

Statue of Liberty, slide 2: "Engineering, Construction, and Crossing the Atlantic." The Statue of Liberty – Ellis Island Foundation Inc. 27 July 2017. http://www.libertyellisfoundation.org/statue-history

Statue of Liberty, slide 6: "The New Colossus." National Park Service. 27 July 2017. https://www.nps.gov/stli/learn/historyculture/colossus.htm

Susan B. Anthony, slide 6: "A Century of Lawmaking for a New Nation: U.S. Congressional Documents and Debates, 1774–1875." The Library of Congress. 27 July 2017. https://memory.loc.gov/cgi-bin/ampage?collId=llsl&fileName=014/llsl014.db&recNum=389

Susan B. Anthony, slide 7: "The Women's Suffrage Movement." National Susan B. Anthony House & Museum. 2013. 27 July 2017. http://susanbanthonyhouse.org/her-story/suffrage-movement.php

The Thirteenth Amendment: Christopher Klein. "Congress Passes 13th Amendment, 150 Years Ago." History. 20 Jan. 2015. 27 July 2017. http://www.history.com/news/congress-passes-13th-amendment-150-years-ago

Theodore Roosevelt, slide 2, quote 1: John A. Gable. "Roosevelt, Theodore." World Book Advanced. 27 July 2017. http://www.worldbookonline.com/advanced/article?id=ar474860&st=roosevelt,%20theodore&gr=Welcome+to+World+Book%21

Theodore Roosevelt, slide 2, quote 2: "Theodore Roosevelt, Sr." National Park Service. 26 February 2015. 27 July 2017. https://www.nps.gov/thrb/learn/historyculture/theodorerooseveltsr.htm

Theodore Roosevelt, slide 2, quote 3:"Quotations from the speeches and other works of Theodore Roosevelt." Theodore Roosevelt Association. 27 July 2017. http://www.theodoreroosevelt.org/site/c.elKSIdOWIiJ8H/b.9297493/k.7CB9/Quotations_from_the_speeches_and_other_works_of_Theodore_Roosevelt.htm

Theodore Roosevelt, slide 6: "Where It All Started: Theodore Roosevelt National Park." Discovering Adventure. 16 Oct. 2015. 27 July 2017. https://sites.psu.edu/gorgasnationalparks/2015/10/16/where-it-all-started-theodore-roosevelt-national-park/

Theodore Roosevelt, slide 7: Joseph R. Ornig. "My Last Chance to Be a Boy: Theodore Roosevelt's South American Expedition of 1913 to 1914." Louisiana State University Press: Baton Rouge, 1994, page 3.

Thomas Jefferson, slide 4: "The Declaration of Independence." UShistory.org. 27 July 2017. http://www.ushistory.org/DECLARATION/document/

Thomas Jefferson, slide 6: "The Embargo of 1807." Digital History. 27 July 2017. http://www.digitalhistory.uh.edu/disp_textbook.cfm?smtID=2&psid=2986

U.S. Constitution: "Preamble." Cornell Law School. 27 July 2017. https://www.law.cornell.edu/constitution/preamble

Ulysses S. Grant, slide 2: "Ulysses S. Grant's Reflections on the War." Smithsonian Source. 27 March 2017. http://www.smithsoniansource.org/display/primarysource/viewdetails.aspx?PrimarySourceId=1047

Ulysses S. Grant, slide 4, quote 1: Brooks D. Simpson. Ulysses S. Grant: Triumph over Adversity. Zenith Press: Minneapolis, 2014, p. 79.

Ulysses S. Grant, slide 4, quote 2: "Battle of Fort Donelson." Britannica. 27 July 2017. http://kids.britannica.com/oscar/article-9030913

Ulysses S. Grant, slide 4, quote 3: "U.S. Grant: Warrior (2011)." PBS. 27 July 2017. http://www.pbs.org/wgbh/americanexperience/features/transcript/usgrant-transcript/

Ulysses S. Grant, slide 7: Edward J. Blum and W Scott Poole. Vale of Tears: New Essays on Religion and Reconstruction. Macon, Georgia: Mercer University Press, 2005, p. 227.

Uncle Sam, slide 4, quote 1: "I Want You Poster." Smithsonian National Museum of American History. 27 July 2017. http://amhistory.si.edu/militaryhistory/collection/object.asp?ID=548

Uncle Sam, slide 4, quote 2: "The Most Famous Poster." Library of Congress. 27 July 2017. https://www.loc.gov/exhibits/treasures/trm015.html

Uncle Sam, slide 4, quote 3: "Britons. Join Your Country's Army!" Imperial War Museums. 27 July 2017. http://www.iwm.org.uk/collections/item/object/16577

Washington Monument, slide 6: Jonas Viles, ed. Letters and Addresses of George Washington. The Unit Book Publishing Company: New York, 1908, p. 416.

Washington Monument, slide 7: "History & Culture." National Park Service. 27 July 2017. https://www.nps.gov/wamo/learn/historyculture/index.htm