Discussed are the results of interviews with 63 Australian children (interviewed in English) and 62 Nigerian children (62 interviewed in English and 60 interviewed in Yoruba) to determine how they used number concepts in discussing five demonstrations manipulating physical matter. Differences between the two groups are considered. (RH)

Activities with number cards can provide a wide variety of exploratory experience. Sequences, addition, subtraction, counting and change, and arrays with number cards are discussed. (MNS)

How to develop multiplicative magic squares is discussed. Various types of numbers are used in the examples. (MNS)

The focus is on multi-step problems, with suggestions on helping students understand the mathematical relations, decide which computational procedures to use, and identify the sequence in which computations should be performed. An activity to aid understanding of variables is also included. (MNS)

Described is a simple algorithm that can be used for the input, arithmetic manipulation, and output of large integers in their exact representations. Three BASIC programs are included that apply this method to the problem of multiplication of large integers, computation of factorials, and the generation of palindromic integers. (MNS)

Tests children for the effects of prior knowledge on the amount of learning that occurs after a training period focusing on either number skills or logical operations. No relationship existed between the amount children learned and their pretraining knowledge or the amount learned and their developmental level. (Author/BB)

Descriptions of eight NIM games are presented, with illustrations. (MNS)

Tests for divisibility in bases 2 through 10 are presented. Two strategies used by a group of fourth-year students are described. (MNS)

Some background information and guidelines on computer generation of random numbers is presented. Sections concern ways of generating random numbers and descriptions of statistical tests. (MNS)

Fractal geometry is explored, with sections on snowflakes and flow snakes, Mandelbrot's definition of fractal, and other fractals. (MNS)

How the manipulative aid called the "10 frame" can be used to teach the number combinations for 10, the addition facts that bridge 10, and the place value nature of our number system is described. (MNS)

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)

Research on college students' ability to estimate means and variances for sets of data showed that they were more able to estimate means, and that various characteristics of the data (e.g. magnitude of numbers) influenced the accuracy of estimates. (SD)

This article suggests some criteria to consider when using a concrete representation to support the treatment of a mathematical concept or sentence. (DT)

A method of using a diagram to investigate properties of fractions is described. (DT)