

Credits
FOSS Staff at the Lawrence Hall of Science, University of California, Berkeley
Linda De Lucchi, Codirector
Larry Malone, Codirector
Kathy Long, Assessment Coordinator and Curriculum Developer
Brian Campbell, Curriculum Developer
Erica Beck Spencer, Curriculum Developer
David Lippman, Program Manager
Delta Education Staff
Editorial Director, Elementary Science: Bonnie A. Piotrowski
Project Team: Mathew Bacon, Jennifer Apt, Sandra Burke, Joann Hoy, Jacquelyn Lachance, Angela Miccinello
Cover and Series Design
Dinardo Design LLC, Concord, MA
Photo Credits
Cover: © Brykaylo Yuriy/Shutterstock; Title Page: © iStockphoto/Brett Hillyard; Pages 3–5: © zulufoto/Shutterstock (background); Page
3: © iStockphoto/Joe Peragino (top); © Planetary Visions LTD/Science Photo Library (bottom); Page 4: © Larry Malone/Lawrence Hall of
Science; Page 5: © iStockphoto/Warwick Lister-Kaye (left); © Larry Malone/Lawrence Hall of Science (top & middle); © Lawrence Hall of
Science (bottom); Page 6: © optimarc/Shutterstock (top); © iStockphoto/Skip Odonnell (bottom); Page 7: © iStockphoto/Mark Evans (top);
© iStockphoto/Vladimir Vladimirov (left); © iStockphoto/Mark Evans (right); Page 8: © iStockphoto/Lisa Kyle Young (top); © iStockphoto/
fotoVoyager (left); © Larry Malone/Lawrence Hall of Science (bottom); Page 9: © iStockphoto/José Luis Gutiérrez (top); © Larry Malone/
Lawrence Hall of Science (bottom); Pages 10–11: © John Quick/Delta Education; Page 12: © iStockphoto/Boris Yankov; Page 13: ©
iStockphoto/Jill Fromer; Page 14: © Lawrence Hall of Science (left); © Harry B. Lamb/Shutterstock (top); © iStockphoto/Johnny Lye (bottom);
Page 15: © iStockphoto/Alexandra Draghici (top); © iStockphoto/MBPHOTO, INC. (bottom); Page 16: © Neale Cousland/Shutterstock; Page
17: © iStockphoto/Dan Kite (top); © Mark Karrass/Corbis (bottom); Page 18: © iStockphoto/Carolina Garcia Aranda; Page 19: © Wouter
Tolenaars/Shutterstock; Page 20: © iStockphoto/Jamie Farrant (background); © iStockphoto/Joachim Angeltun; Page 21: © Lawrence Hall
of Science; Page 22: © Dave Bradley Photography, Inc./Delta Education (top); © Lawrence Hall of Science (bottom); Page 23: © Lawrence
Hall of Science (top); © iStockphoto/peregrine (bottom); Page 24: © iStockphoto/Pauline S Mills; © iStockphoto/Erlend Kvalsvik (inset);
Page 25: © iStockphoto/Ray Roper (top); © iStockphoto/MaxFX (bottom); Page 26: © iStockphoto/Phil Dickson (top); © iStockphoto/Shaun
Lowe (bottom); Page 27: © Corbis/Museum of the City of New York; Page 28: © Lawrence Hall of Science (top); © iStockphoto/Sherwin
McGehee (bottom); Page 29: © iStockphoto/Milos Luzanin (top); © iStockphoto/Sergey Korotkov (bottom); Page 30: © Stephen J. Krasemann/
Photo Researchers, Inc.; Page 31: © Ivaschenko Roman/Shutterstock (top); © Sergio Stakhnyk/Shutterstock (bottom); Page 32: © Sundraw
Photography/Shutterstock (top); © BMJ/Shutterstock (bottom); Page 33: © iStockphoto/Arturo Limon (top left); © Laurie Meyer/Delta
Education (top right); © Andrew Koturanov/Shutterstock (bottom left); © David Lee/Shutterstock (bottom right); Page 34: © behindlens/
Shutterstock (top); © Jean Frooms/Shutterstock (bottom); © Laurie Meyer/Delta Education (inset); Page 35: © Mariusz Gwizdon/Shutterstock
(top); © Lisa F. Young/Shutterstock (bottom); Page 36: © Mark C. Burnett/Photo Researchers, Inc.; Page 37: © bhowe/Shutterstock (top); ©
iStockphoto/miljko; Page 38: © psamtik/Shutterstock; Pages 39–40: © Lawrence Hall of Science; Page 41: © happydancing/Shutterstock; Page
42: © Matt Gibson/Shutterstock (top); © Pletnyakov Peter/Shutterstock (left); © beerkoff/Shutterstock (right); Page 43: © iStockphoto/christie
& cole studio inc. (left); © PhotoAlto/Fotosearch (right); Page 44: © David Davis/Shutterstock; Pages 45–46: © Scott MacNeill/Delta Education;
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Shutterstock (inset); Page 49: © Scott MacNeill/Delta Education; Page 50: © Chiyacat/Shutterstock (top); © kukuruxa/Shutterstock (bottom);
Page 51: © Tom Roche/Shutterstock (top); © Jason Patrick Ross/Shutterstock (bottom); © Johnny Adolphson/Shutterstock (bottom inset);
Page 52: © Lijuan Guo/Shutterstock (top); © Guo Yu/Shutterstock (left); © Patrick Poendl/Shutterstock (right); © studio23/Shutterstock (right
inset); Page 53: © Mark Carthy/Shutterstock (top); © Saraporn Bamrungchart/Shutterstock (bottom); Page 54: © Christine Langer-Pueschel/
Shutterstock; Page 55: © FloridaStock/Shutterstock; Page 56: © Ruud Morijn Photographer/Shutterstock (top); © hddigital/Shutterstock
(bottom); Page 57: © Miks Mihails Ignats/Shutterstock; Page 58: © Ruud Morijn Photographer/Shutterstock; © oilchai/Shutterstock (inset);
Page 59/Back Cover: © Zacarias Pereira da Mata/Shutterstock; Page 60: © patjo/Shutterstock; Page 61: © Moshe Alamaro (top); © Tom
Wang/Shutterstock (bottom); Page 62: © Scott MacNeill/Delta Education; Page 63: NASA; Page 64: © iStockphoto/DenGuy; Page 65: ©
iStockphoto/Graffizone; Page 66: © iStockphoto/Jaap Hart; © iStockphoto/Dan Moore (inset); Page 67: © Jaimie Duplass/Shutterstock; Page
68: © iStockphoto/Desrosi (left); © iStockphoto/Charles Schug (right); Page 69: © Dave Bradley Photography, Inc./Delta Education (top);
© PHOTOCREO Michal Bednarek/Shutterstock (bottom); Page 70: © Brian Kinney/Shutterstock; © gillmar /Shutterstock (inset); Page 71: ©
iStockphoto/Danielle Easley (top); © iStockphoto/David Jones (left); © iStockphoto/Mayumi Terao (right); Page 72: © iStockphoto/Eduard
Härkönen (background); © Scott Rothstein/Shutterstock (left); © Yellowj/Shutterstock (middle); © iStockphoto/Josef Becker (right); Pages
73–76: © 123rf.com (background); © MIT Museum, Cambridge, MA; Page 77: © Sodis/Eawag; Page 78: © Lawrence Hall of Science; Pages
79–80: © Vinka Oyanedel-Craver; Page 81: © Susan Amrose; Page 82: © Marcin Balcerzak/Shutterstock (top); © Goodluz/Shutterstock
(bottom); Page 83: © iStockphoto/Chris Crafter (left); © iStockphoto/Doug Webb (right); Page 84: © iStockphoto/Frank van den Bergh (top
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© Michael Bernitsas (bottom); Pages 87–88: © Michael Bernitsas; Page 89: © iStockphoto/jian wan (left); © iStockphoto/paparazzit (top); ©
iStockphoto/Peterclose (bottom); Page 90: © Delta Education.