By Laurie E. Westphal Packed with more than 350 science definitions that every student must know, this is an essential science homework helper and reference guide for assignments, projects, and experiments. Most definitions have illustrations. Includes Earth, Physical, Life, and Space Science chapters and more. Complete with commonly used formulas, measurement conversions, and charts. Paperback. 7"x 9". 136 pgs. Gr. 4-9.