Material included in this bulletin provides an overview of research studies which pertain to teaching addition and subtraction of whole numbers in the primary grades. The studies mentioned relate directly to the following questions: (1) What foundation for addition and subtraction do children have upon entering school? (2) What is the relative difficulty of addition and subtraction facts? (3) Should addition and subtraction be introduced at the same time? (4) What type of problem situation should be used for introductory work with subtraction? (5) How can number facts be taught effectively? (6) How should subtraction with renaming be taught? (7) What is the role of drill in teaching addition and subtraction? A list of selected references is supplied at the end of the paper. (FL)