This very well done, highly engaging series discusses the scientific principles behind the various subjects and is liberally illustrated with both photographs and illustrations. All of the books feature experiments and recommended websites for additional information. Information is provided on such topics as the states of matter, famous scientists, and atoms in a conversational, not pedantic, tone. This series will be useful for both student research and for students with independent interest in these topics. A[n] engaging resource, especially for reluctant readers. . . . Recommended.