This book is part of a book series called National Geographic Science Chapters .

This book has been graded for interest at 6-9 years.

There are 40 pages in this book. This is a chapter book. Publishers market early chapter books at readers aged 6-10 years. This book was published 2007 by National Geographic Society .

Monica Halpern is a children's book writer who has penned several National Geographic Science Chapters. She is also the author of Railroad Fever: Building the Transcontinental Railroad, 1830-1870 (which received a starred review in School Library Journal ) and Moving North: African Americans and the Great Migration, 1915 - 1930 . Halpern lives in Boston, Massachusetts.