Two studies trace children's acquisition of counting as a means to extract, compare, and reproduce number from arrays of objects. Study 1 examined 3-, 4-, and 7-year-olds' use of counting to compare and reproduce arrays numerically. In study 2, nine of the 3-year-olds from the study 1 were retested after 12 and 18 months. (Author/JMB)

A discussion of computer errors and round-offs is given with the conclusion that attempts to get rid of these almost always result in generating more errors. (MN)

For journal availability, see EC 092 078.

The evolution of complex numbers is described, followed by discussion of some lessons that can be learned from this story, as with other stories from the history of mathematics. Suggestions for teachers about incorporating history into mathematics instruction are included. (MNS)

Presents a sociohistorical analysis of the development of a set of basic information technologies, namely, abstract symbols for quantities of space and time, and the formulation of computational strategies. Shows how numbers and geometry can be seen to reflect increases in a society's knowledge and social organization. (ARH)

Presented is a brief overview of Japanese education followed by specific ideas about important considerations in the teaching of mathematics in elementary grades. Examples are given for teaching flexibility in mathematical thinking. (RH)

Procedures for developing a variety of magic squares and magic triangles are given. A bibliography with references containing more ideas is included. (RH)

Discussed is research on children's understanding of zero and infinity and teaching suggestions for improving understanding. (RH)

Empty food containers can be used to have students devise mathematical problems. Sample questions that might be asked about two food boxes are included. (MNS)

Described is a computer program that uses an interesting matrix method to generate Pythagorean triples. Program listings and output for two programs are included. (MNS)

Past beliefs about numbers are presented, concerning odd, even, perfect, prime, and amicable numbers; specific numbers between 1 and 13; gematria or assigning values to letters; and numerology. (MNS)

Microcomputer programs that help students calculate permutations and combinations are developed. Listings of five programs are included. (MNS)

The progression from simple interest to compound interest leads naturally and quickly to the number e, involving mathematical discovery learning through writing programs. Several programs are given, with suggestions for a teaching sequence. (MNS)

Exploring the strategies used in simple games for two players is discussed. Six games are briefly described, followed by suggestions for analyzing them. (MNS)

Presents activities designed to help young children learn basic notions of estimation (or "about how much"). The subcategories included in the article are: "About How Many"; "About How Long or How Far"; "About How Big"; and "About How Many with Very Large Amounts." (MNS)