As with many True Books, this one starts with two statements, only one of which is true.  Jam-packed with information, definitions, and explanations, readers will learn many basic facts geologists know.  The first chapter tells how the scientific method works to help scientists learn.  Throughout the book are small experiments to test rock properties – crystal color, streak, and hardness.  When explaining how rocks are made, the three basic types of rocks (sedimentary, metamorphic, and igneous) are described.  More experiments show how layers build up and break down.  This book provides a great balance between information and experimentation.  Experiments are well explained, include photographs, and provide a method of recording observations.  Other photos show rocks in various land forms.  In the back are recommended books to read, two excellent websites for further learning, two places to visit (complete with addresses and websites), a glossary with pronunciation clues, index, photo credits, and a bio. of the author.  Recommended addition to elementary school libraries and/or classroom collections.