The Pre-Algebra Tutor DVD series teaches the fundamentals of pre-algebra through step-by-step example problems that progress in difficulty. Emphasis is placed on giving students confidence in their skills by gradual repetition so that the skills learned are committed to long term memory. This program covers the important topic of teaching students how to subtract integers from one another. Students will learn how to subtract positive and negative numbers using simple rules to illustrate the process. The number line is used to reinforce the material. Grades 9-College. 37 minutes on DVD.