Do your students think a triangle can be constructed from any three given line segments? Do they believe that a transformation affects only the pre-image--not the whole plane? Do they understand that examples--no matter how many they find--cannot prove a conjecture but one counterexample is sufficient to disprove it? "What tasks can you…

"Setting the Stage with Geometry" is a new math program aligned with the National Council of Teachers of Mathematics (NCTM) standards that is designed to help students in grades 6-8 build and reinforce basic geometry skills for measuring 2D and 3D shapes. Developed by The Actuarial Foundation, this program seeks to provide skill-building math…

Presents an activity, involving pentagons and using a figure manipulator such as The Geometer's Sketchpad, that requires students to reason geometrically without making unsubstantiated assumptions based on diagrams. (MKR)

In this article, the author describes two Powerpoint presentations designed to help visual learners calculate the circumference and the area of a circle. In particular, the author describes how these presentations can be used to establish mental images that can help pupils to understand, and so recall, the principles that underlie the formulae for…

Discusses several dynamic geometry constructions with rectangles. Advocates use of software like Geometer's Sketchpad and Cabri Geometry for fostering fresh insight into traditional geometric theorems. Illustrates problem-solving methods not possible with pencil and paper. (MTE)

Presents a teaching experience with high school students in geometry class using hand signals that reinforce meaning of geometric concepts. (KHR)

Presents an activity centering on Baravelle spirals in regular polygons to review and connect a number of algebraic and geometric topics, as well as to involve students in formal calculations, visualization, pattern discovery, series, estimation, and recursion. (MKR)

Details are given about some activities designed to help students convey three-dimensional objects into two-dimensional representations by constructing and drawing buildings of blocks. (MP)

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)

Presents activities focusing on the use of visual perspectivity. Includes reproducible student worksheets. (MKR)

Focuses on two types of symmetry, rotation and reflection, their underlying structure as a mathematical group, and their presence in the designs of diverse cultures. Illustrates patterns created by applying these symmetry operations that offer students a visual image which forms the axiomatic basis of algebra. (KHR)

Presents an introduction to the study of projective geometry, including a definition and some analagous examples using the overhead projector. Illustrates the principle of duality, Desargues' theorem, Poppus' theorem, and Pascal's theorem. (TW)

A lesson plan for first-grade children beginning to learn English describes an activity using manipulatives and visual aids to develop recognition of three geometric shapes (circle, square, rectangle), their names, and a few additional words in English (e.g., "bag,""table,""door"). Students are grouped at tables of four to six and provided with…

Presents an argument for using dot paper rather than geoboards at postelementary levels to study perimeter, area, congruence, similarity, and other geometric ideas. Emphasizes need for students to be active learners. (GW)

A Navajo blanket design was constructed on a bulletin board and on geoboards. Then a program was written in LOGO to construct the pattern. Both top-down and bottom-up techniques were used. Students were encouraged to make their programs more efficient by utilizing repeat and subprocedures. (GW)