Describes a study which compares the abilities of 130 first graders in responding correctly to open (Computational) addition exercises to their abilities in responding to equivalent problems stated in the closed form. No statistical difference between levels of correct responses to opened or closed exercises was indicated. (PR)

Two sequences of activities were developed to provide instruction on the algorithms for addition and subtraction of two-digit numbers. In the integrated sequence (I) the mechanics of "carrying" and "borrowing" were treated as a single process "regrouping." In the sequential treatment (S) the addition algorithm was developed before the subtraction…

Two sequences of activities were developed to provide instruction on the algorithms for addition and subtraction of two-digit numbers. In the integrated sequence (I) the mechanics of "carrying" and "borrowing" were treated as a single process "regrouping." In the sequential treatment (S) the addition algorithm was developed before the subtraction…

An investigation is given of exceptions to the rule for adding fractions. The use of such exceptions in instruction is discussed. (MP)

The purpose of this study was to find out what difficulties Nicaraguan children encounter in doing addition and subtraction exercises. The results were used in the design of radio lessons in mathematics for elementary school. The performance on addition exercises is analyzed with a view toward identifying the distinct skills that are required by…

A technique for adding and subtracting integers is presented as an alternative to the number line. White and black chips are used to represent positive and negative integers, respectively. (MP)

Adding the number directly, one after another, was compared to adding the numbers by looking for combinations of ten. The Direct method was faster, but the two methods were equally accurate. (JT)

First graders at three different schools were individually interviewed to determine their understanding of missing addend problems. Details of the interview are provided. Behaviors separating successful from unsuccessful students, students' number conservation ability, and the abstractness of missing-number problems are discussed. (DT)