Problems involving divisibility, the ten coin triangle, five times a week with 4 D, a nomogram for the lens formula, the box and ladder problem, chains of circles, tessellating hexagons, topological woggles, and numbers of triangles are discussed. (CT)

The authors present an enrichment topic appropriate for use in grade 12. A mathematical system is defined using integer 3-tuples and it is shown that this system is a field isomorphic to the rational numbers. The unit is useful for illustrating the abstract nature of mathematics. (CT)

A study designed to investigate a method examining some of the processes involved in students' forming of mathematical concepts in an experimental mathematics course. Results suggest that the card sorting task offers a useful tool for use in evaluation programs. (FL)

The problem of inscribing a square in a semicircle and related problems are discussed. Solutions to the problems are provided. (FL)

A teaching method which involves student participation to the extent that students teach other students in their classroom is described. An outline of how this technique should operate in a general mathematics class is presented. (FL)