page 46: Student at Montgomery Blair High School, Silver Spring, Maryland, Robert Allen Strawn, photographer.

page 49: Students at Piney Branch Elementary School, Takoma Park, Maryland, Robert Allen Strawn, photographer.

page 51: Students at Eastern Middle School, Silver Spring, Maryland, Robert Allen Strawn, photographer.

page 54: Trilobite, David McGrath, photographer, © Photo Archives, Denver Museum of Natural History.

page 60: Students and teacher, Milton Hershey School, Hershey, PA, © Blair Seitz.

page 61: Student at Piney Branch Elementary School, Takoma Park, Maryland, Robert Allen Strawn, photographer.

page 64: Draft Growth-of-Understanding Map. Benchmark for Science Literacy, AAAS.

page 71: Graphic by Leigh Coriale Design and Illustration.

page 72: Graphic by Leigh Coriale Design and Illustration.

page 73: Graphic by Leigh Coriale Design and Illustration.

page 83: Graphic by Leigh Coriale Design and Illustration.

page 84: Graphic by Leigh Coriale Design and Illustration.

page 89: Graphic by Leigh Coriale Design and Illustration.

page 102: Graphic by Leigh Coriale Design and Illustration.

page 104: Books, © TSM/Tom Stewart 1995.

page 105: Keyboard, NAP Image Archives.