Construction of colorful braided polyhedra can provide upper elementary students with enjoyable geometric experiences. (SD)

Paper-folding activities demonstrate properties of the conic sections and equilateral triangles. (SD)

Problems related to the division of sides of triangles into congruent parts are discussed. (SD)

The geometry curriculum at the elementary school level is discussed. Details of five different units on geometry, each stressing space orientation, are given. (DT)

The use of paper folding to study properties of geometric solids is discussed. (SD)

After students learn that it is impossible to trisect an angle using compass and straight-edge, students are introduced to the trisectrix curve which accomplishes the trisection. (SD)

Using license plates to generate random number pairs, students can calculate an approximate value for pi. The author views this approach as easier to understand than Buffon's needle. (SD)

The isometric grid geoboard can be used to demonstrate the nine-point circle theorem. (SD)

The value and technique of pre-geometry and geometry instruction in the primary grades are discussed. Geometric concepts such as open and closed figures, connectedness, similarity, congruence, straightness, and angle are presented through suggested activities, lesson plans, and evaluation procedures. (SD)

Finding the shortest route between two points can be approached by vector methods. Several types of matrices modelling a map of 6 cities are described. (SD)

Activities involving estimation of the number of objects in a configuration can motivate students to consider parametric models. (SD)

Properties of cones can be studied by considering the circular sector obtained by slitting and unrolling the surface of the cone. (SD)

Activities in which students make and prove conjectures and devise their own geometric axiom systems are discussed. (SD)

The nature of measurement, the standard measurement concepts are discussed in terms of children's preconceptions and activities for building measurement concepts through primary school instruction. A broad range of activities including counting, computation, calibration, and relating measure to size is presented. The metric system is briefly…

After a unit on Euclidean geometry which stresses both the development of intuition and the use of deductive methods, non-Euclidean concepts are introduced by having students read and consider science fiction stories. (SD)