The method described here converts a given problem in a base other than ten to a related problem in base ten, solves the related problem in base ten, and converts the answer back to the original base. Limitations are discussed. (MP)

Algorithms are developed and presented for the addition and multiplication of positive rational numbers using only their repeating decimal representation. (MN)

Observations of students working with subtraction and division are reported. The instructional situation and goals of the teacher are discussed. (SD)

An approach close to the original Greek geometric point of view regarding the question and proof of the irrationality of the square root of two is given. (MN)

The author gives a method for involving students in developing and verifying elementary number theory hypotheses by studying areas and perimeters of primitive pythagorean triangles. (MN)

Characteristics of the number seven, which relate to many different areas of mathematics, are discussed. (JT)

A successful method for teaching place value is described. (JT)

The concept of even and odd integers is explored through the use of fractions. (JT)

Guidelines for teachers to better use manipulatives in the teaching of mathematics to learning disabled learners are offered including a rationale for manipulatives, selection crteria, principles underlying productive use of manipulatives, and making the transition from the concrete to the symbolic. Suggested materials and distributors are listed.…

The article offers an interpretation of "specially designed instruction" in arithmetic computation for learning disabled students which challenges overreliance on paper-and-pencil methodologies, rule-oriented procedures, and traditional sequences. Long division is used as an example of developing conceptual understanding to undergird computation.…

An application of spreadsheets, not specific to any particular spreadsheet, is provided. It provides an exploration involving numbers in the form of 3x3 magic squares and 3x3 magic cubes. Strategies for their use are noted. (MNS)

Activities are presented that focus on attributes of numbers. The activities highlight such attributes as more than, equal to, greater than, less than, LCM, prime and factor. The activities provide practice in motivational game-oriented situations. (RH)

The number charts described in this article have been used successfully with elementary students as young as first graders to teach the concepts of even and odd numbers. Students construct charts and then answer a series of questions about the patterns that they observe. (RH)

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)