A student noticed an interesting fact about the base two numerals for perfect numbers. Mathematical explanations for some questions are given. (MNS)

The Euclidean algorithm for finding the greatest common divisor is presented. (MNS)

Ideas for teaching the concepts of percentage, recognition of patterns in percentages, percentage as a special ratio, ways of finding percentages, and fractional percentages are presented. (MNS)

How to find and classify positive integral solutions to 1/a + 1/b = 1/c in beginning and advanced algebra classes is described. The computer finds the solutions, but students practice algebraic manipulation as they analyze the solutions for patterns. Extensions to challenge more capable students are included. (MNS)

Heavy emphasis is placed on development of understanding of arithmetic in this mathematics curriculum prepared specifically for Navajo children and intended for use in reservation schools. Materials are presented so that only when a given concept is understood are skills associated with it and a written format introduced. Learning activities…