TOMECEK, Stephen M. Tools &; Machines . 182p. ISBN 978-1-60413-171-0 . LC 2009022332. ea vol: (Experimenting with Everyday Science Series). diags. photos. bibliog. further reading. glossary. index. Web site. CIP. Chelsea House . 2010. PLB $35. Gr 6 Up Each of these texts offers 25 easy-to-perform activities that illuminate scientific principles. After the same brief series introduction in each volume, Tomecek devotes several pages to a comprehensive outline of safety precautions ranging from preparing for an experiment to washing hands and disposing of chemicals properly at the conclusion of an activity. Topics in Music include the history of music, various instruments, and how scientific principles explain the creation of sounds. Tools discusses levers, pulleys, and meters and explains how people use them in their daily lives. Both books include four to six experiments that can be performed in the classroom or at home. A brief introduction, time required, a list of materials, and a safety note precede the step-by-step instructions. Questions in the final "Analysis" and sections titled "What's Going On?" and "Our Findings" offer explanations for the results. Following each experiment are additional comments on the science behind the experiment and link to the one that follows. Photographs, simple diagrams and illustrations, and sample data tables appear throughout, and the layouts are clear and colorful. Maren Ostergard, King County Library System, Issaquah, WA