So much of life is synthetic that it is a pleasure to introduce youngsters to natural products like goose down, lanolin, and an antidote gingerly extracted from a deadly snake. This colorful book encourages that sort of scrutiny. Challenging early science students to think beyond the obvious, this is one of six recently published titles in an exceptional series called "Whose Is It?" all with tests on the Accelerated Reader list. The book consists of eight questions and allows plenty of room for thinking and discussion. Answers are presented in simple, clear text, accompanied by a small fun fact box with additional information for higher-level readers. More challenging still is the invitation to a specially-designed children's search engine which leadswhen the code provided is enteredto a handful of safe Web sites for further research. Throw in a page full of top-notch trivia on the animals featured, an index, a vocabulary list and a bibliography, and the package becomes "edu-tainment" at its best. 2004, Picture Window Books, Ages 4 to 8.