Three teaching ideas are discussed: the improvement of ditto reproduction, and exploration of congruent triangles, and an intuitive introduction to the concept of limit. (MP)

Activities designed to help pupils develop spatial abilities with cubes and right angles are presented. Instructions for manufacturing the special three-dimensional objects described are included. (MP)

Defines cases, symmetry, and analysis as the heuristic strategies most commonly employed by a select group of high school students in solving novel mathematics problems. Confirms that the utilization of heuristics appears to be problem-dependent. Describes the procedure, actual problems, results, and recommendations of the study. (SB)

Offers a problem for teachers to try with their students. The problem is presented visually as a row of 15 connected squares and the task is to determine the number of rectangles. The goal is to encourage teachers to reflect on students' work and analyze classroom dialogue. (PVD)

Describes an extended investigation of polygons and polyhedra which was conducted in response to a challenge posed in Focus, a newsletter from the Mathematical Association of America (MAA). Students were challenged to construct a polyhedron with faces that measure more than 13 inches to a side. Outlines the process, including the questions posed…

Presents activities to help students develop the notion of geometric congruence and similarity in a hands-on environment. (ASK)

Discusses the interconnection among the various modes of the TI-92 calculator (geometry, data graphing, function graphing, and algebra) and how the power of visualization is extended to provide multiple approaches to complex problem situations. Provides a graphing problem with illustrations and results. (AIM)

Describes a study of third-grade students (N=38) that investigates the development of linear measurement concepts. Three levels of strategies were identified: visual guessing, hash marks, and no physical partitioning. Students who connected numeric and spatial representations proved to be the better problem solvers. Contains 22 reference. (DDR)

Based on a college-level geometry course, presents practical suggestions for integrating exploratory computer applications into the mathematics classroom. Reveals that students need more experimental time with technology to reduce anxiety, and assessments need to be developed and implemented to tap the outcomes of problem solving and higher level…

Presents to second graders the concept of an n-gon, characterized by a commutative diagram which is composed of four ways of judging a given figure. Observes that some children gave persuading arguments containing a critical idea and the concept formation corresponding to a structure-preserved transformation in the diagram. (AIM)

Describes an activity in which geometry and trigonometry are studied using pyramids. Identical model pyramids are constructed from card stock, along with pyramids of different proportions and cuboids to use as controls. Also includes an investigation of some apparently non-scientific claims. (DDR)

Features articles about physical therapy and its history as related to geometry through measurement of body angles. Includes open-ended worksheets for mathematics activities that introduce students to angle measurement, data analysis, and mathematical tools. Activities include: (1) Making Your Own Goniometer; (2) Range of Motion; (3) Active versus…

Presents two ancient problems, trisecting any angle and dividing a circle into any number of equal parts. Illustrates how to use these problems to prompt students to think broadly and creatively about problems instead of letting the apparent boundaries of the problem limit their thoughts. Combines three-dimensional solutions to the problems to…

Describes an engaging project in which students have to design and construct a three-dimensional candy box that would appeal to children. Requires students to make the box out of prisms, pyramids, or cylinders, determine the surface area and volume of the solids, and write a persuasive business letter. (YDS)

Investigates uses of interactive geometry software to enhance students' understanding and reasoning about two-dimensional shapes. Describes basic principles that underlie high-quality geometry instruction. Presents examples that illustrate how appropriate use of dynamic software can enhance students' geometric reasoning. (KHR)