The patterns of the coefficients in the expansion of (x + y +z)n are discussed, and a recursive property is developed as a generalization of the Pascal triangle. (MP)

Techniques that can be used in solving various mathematical problems are illustrated by an optimization problem and the accompanying model and solution. (MP)

Describes zoo creatures of interest to recreational mathematicians. Includes the geometrical symmetries of micro- and macroorganisms, topological studies, and imaginary creatures of scientific interest. (MA)

Some misconceptions about "squares" encountered among college students as they attempt to master appropriate subject matter in preparation for teaching elementary grades are presented. (MN)

A method for finding the area of a circle is described which involves finding points on the circle with the aid of a calculator and then applying the formula for the area of a polygon. (MN)

A sequence of ellipses and a sequence of hyperbolas, both graphically approaching some parabola, are expressed algebraically and then shown to approach the parabola. (MN)

The author offers a new puzzle requiring that the mixed set containing all the members of the set of trihexagons and the set of tetrahexagons be fitted inside a star-shaped outline. (MN)

Several geometric and trigonometric proofs are discussed. These proofs were selected from a larger group because of their instructional value promoting enrichment or generalization. (SD)

Activities growing out of a study of Euler's formula are described. (SD)

Eight geometric construction problems with some unusual constraints are presented and then solved using only an unmarked straightedge and a compass. (JT)

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)

The opportunity for students to develop formulas that involve tangent lines to a circle and the Pythagorean Theorem and to use approximation and common sense is provided in a suggested distance-to-horizon problem. (MN)

The good and bad points of Euclidean geometry and transformation geometry are briefly surveyed with emphasis on the teachability of Euclidean geometry and the mathematics of transformation geometry. (MN)

The author examines certain areas of confusion which arise in the teaching of linear equations for lines. (SD)