Some properties of perfect numbers are illustrated. (SD)

Activities in which the claims of psychics are evaluated can be used in probability classes. (SD)

Experiments using soap films illustrate some of the most basic theorems concerning networks in a geometric framework. (SD)

Games and puzzles in which a checkerboard can be used to develop mathematical concepts are described. (SD)

A review lesson based on a sports car rally is described and illustrated. It teaches detailed map reading as well as providing drill on any subject desired. Pairing students is beneficial for several stated reasons. Some students may design their own rally for presentation to the class. (Author/KM)

The author describes a series of current economic ideas and situations which can be used in the mathematics classroom to illustrate the use of signed numbers, the coordinate system, univariate and multivariate functions, linear programing, and variation. (SD)

The author observes that the predictor functions determined geometrically by Ranucci (EJ 090 184) can be algebraically derived, and that capable students might enjoy verifying them. Algebraic formulations and derivations are provided. (SD)

By translating inequalities into equations (e.g., x greater than 0 can be written x- absolute value of x = 0) and forming equations for unions and intersections of solution sets, students can develop equations for polygons. The method can be generalized to yield equations in three dimensions. (SD)

Equations or systems of equations can be associated with letters of the alphabet printed in the coordinate plane. Messages can be coded and decoded with a computer or by hand. (SD)

Topics covered include alternate methods for finding LCM and GCF, imaginative word problems, and a primes-breakdown method of factoring quadratics. (MP)

This puzzles uses a crossword format with the entries being factors of given polynomials. (MP)

Classroom activities that provide meaningful practice, and at the same time motivate students, are the subject of this article. Several activities appropriate for first-year algebra are discussed; e.g., a prepared matrix of algebraic numbers, cross-factor puzzles, and number tricks. (MP)

Contained in this column are articles discussing the following topics: cross-number puzzles, an intuitive development of pi, a three-column proof format, and an easily constructed kit to be used in acquainting students with the wrapping function used in introducing circular functions. (MP)

The solution of cubic equations is obtained by constructing intersecting conic sections. Details for a particular cubic are given. (MP)

Topics covered include: a game involving dice, using curve stitching to teach number concepts, and an activity to introduce rectangular coordinate systems. (MP)