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…

In the winter of 1965, an experimental course in Elementary Number Theory was presented to a 6th grade class in the Hosmer School, Watertown, Massachusetts. Prior to the introduction of the present material, students had been exposed in class to such topics from the University of Illinois Arithmetic Project as lattices, number lines, frame…

Discusses a tally device using discs on a paper diagram. Instructions given for number representation, negative values, games, addition and subtraction. (RS)

Suggested activities involving number patterns, using the idea of a number machine." (MM)

The author describes an experiment to compare performance of grade 1-3 children on the various types of open sentence associated with basic number facts, and suggests some explanations for the results obtained. (MM)