The Math Tutor series provides step-by-step instruction in the most common math concepts needed by students of all ages. Included are practice exercises, reviews and vocabulary definitions. Math Tutor: Pre-Algebra Skilss covers factoring, positive and negative numbers, order of operations, variables, exponents and various formulas such as perimeter, area and volume. Correlated to state, national and Canadian provincial standards. 80 pages, grades 6 and up.