The principle of the permanence of the rules of calculation is contrasted with the concretization permanence principle. Both apply to situations where some arithmetical operation known to children for numbers of a certain kind is to be extended to include further numbers. (MNS)

Six activities useful in developing the idea of prime factorization are described. Some of these activities are best done with a calculator. (MK)

Part 2 considers the limit of a sequence and extends this to include ideas such as continuity, derivative, and integral. The discussion concludes with an example of a finite or "counted completely" set, the Fermat primes. (MK)

Suggestions for teaching the concept of division by zero are given. (MK)

Some strategies for avoiding misconceptions about the greatest common factor and the least common multiple are presented. Several alternative methods for computing each are given. (MNS)

Five intuitive explanations of division by zero that arise from the common models used in the elementary school to introduce whole number division are presented. (MK)

Some history, applications, and unique characteristics of zero are discussed. (MK)

Masters of worksheets designed to generate interest in mathematics and provide mathematical experiences that lead to the introduction of the concept of a variable are presented. (MK)

Written for teachers of "liberal arts physics," this article about logarithms outlines a way to review arithmetic skills in manipulating powers, discusses the attitude of physicists toward numbers, and gives an introduction to estimation. (MK)

Presented are suggestions for teaching absolute value using five different definitions of the concept. (MK)

The format of digits in liquid crystal displays (LCDs) on calculators and watches can motivate some simple investigations appropriate for school mathematics. Several sample problems or investigations are provided. (MK)

Ignored concepts of numbers, notation, and operation with rational numbers are described. It is proposed that these be taught in the time now devoted to paper-and-pencil skills made obsolete by calculators. (MNS)

This guide for a mathematics curriculum for grades 1-4 presents topics in sequential order for the entire four-year program. Grade level was not used for separating units; instead, an integrated sequencing of concepts was used in preparing this guide. The relationship between units is specified for the teacher as an explicit mapping of how a…

Suggestions for outdoor mathematics activities include six each for primary-age and intermediate-age children. (MK)

The authors develop the idea of Niven numbers and discuss their potential usefulness in the classroom. A computer program to generate Niven numbers is provided. (MK)