Two mental algorithms, one for addition and one for subtraction, are described. It is felt such algorithms should be taught explicitly. The usual process taught for paper and pencil is seen to inhibit mental arithmetic, and a need to include mental algorithms in the regular mathematics curriculum is promoted. (MP)

Presented is a method of teaching adding and subtracting as an interrelated series of patterns using a number line. Examples of the use of this method as well as the materials necessary are discussed. Applications of the method to multiplication and division are given. (CW)

Presents five activities focusing on mental computation and estimation for the K-3, 3-5, 4-6, and 6-8 grade levels that require the student, acting as a judge, to review solutions to problems and to pronounce and justify a verdict. Provides suggested materials, questions, possible extensions, answers, and worksheets for each activity. (MDH)

Directions are given for preparing a puzzle that may be used to provide practice in computation. (MP)

Allowing students to examine different ways of performing an operation is suggested as a means of increasing their understanding. (MP)

Several ideas for questions and settings for interviews are presented. It is noted that although subtraction is used as an example in each case, most of the material can be easily adapted to the other basic operations. Many problems are noted with standard diagnostic tests and use of them is discouraged. (MP)

This article focuses on the aspect of mental arithmetic that uses thinking strategies that are effective with large numbers as well as basic facts. Two activities are suggested for lack of the four operations. (MK)

A collection of games and puzzles that teachers can use to replace or supplement the usual textbook subtraction examples involving large numbers is given. Most of the nine activities are self-checking. (MNS)

A finger method for subtraction that has proved successful with many young subtraction-troubled mathematics students is presented. (MP)

Masters to be removed and copied are given. The worksheets are designed to reinforce computational skills and the concepts of largest or smallest numbers, as well as to provide practice is using a straightedge. (MK)

Specific instruction in different contexts provide needed background for solving addition and subtraction problems. The categories of problems and relative difficulties are presented, followed by an explanation of a successful instructional sequence. (MNS)

Drill activities for addition, subtraction, multiplication, and division that are derived from the history of mathematics are suggested. (MK)

An experimental program using the calculator in third, fourth, and fifth grades is described. Three example lessons are included, on (1) subtraction with regrouping, (2) estimation, and (3) number theory: Quadratics. (MK)

Problems based on shopping experiences are presented on two posters. Children practice estimation and computation with addition and subtraction. (MNS)

The author argues that children not only can but should create their own computational algorithms and that the teacher's role is "merely" to help. How children in grades K-3 add and subtract is the focus of this article. Grouping, directionality, and exchange are highlighted. (MNS)