Described is a method of teaching geometric constructions. The method relates five basic constructions to the properties of a rhombus. (RH)

Describes some unsolved problems in geometry, as well as some recently solved ones. Indicates that each advance generates more problems than it solves, thus ensuring a constant growth in unsolved problems. (GA)

A detailed proof is given of a theorem that characterizes the vertex sequence of any convex polyhedron and establishes the existence of only 13 Archimedean solids. (MP)

Equations for the conic sections are given, and properties of the conics are discussed. The contributions of Greek mathematicians are reviewed. (DT)

Describes how the concept of similar triangles was taught using an optical method of estimating large distances as a corresponding activity. Includes the derivation of a formula to calculate one source of measurement error and is a nice exercise in the use of the properties of similar triangles. (Author/NB)

Presents an active way for students to learn about SAS, SSS, ASA, AAS, and HL in determining congruent triangles. (Author/NB)

Teaching mathematics with games and puzzles goes back in history. Presents an example with the set theory game called Subset Takeaway in which two players can play. Creates a geometric representation of Subset Takeaway starting with a triangle and going to a three-dimensional simplex. Illustrates the winning strategy in the game and features a…

These Proceedings are a written record of the research presented at the 33rd Annual Meeting of the North American Chapter of the International Group for the Psychology of Mathematics Education (PME-NA 2011) held in Reno, Nevada, October 20-23, 2011. The theme of the conference is Transformative Mathematics Teaching and Learning. The Proceedings…

Geometry theorem proving involves skills that are difficult to learn. Instead of working with abstract and complicated representations, students might start with concrete, graphical representations. A proof tree is a graphical representation of a formal proof, with each node representing a proposition or given conditions. A computer-assisted…

This is one of a series of geometry modules developed for use by secondary students in a laboratory setting. This module, intended to present a treatment of congruent triangles which is not totally axiomatic, contains six sections: (1) Draw vs. Construct; (2) Triangle Construction; (3) Arguing for Congruence; (4) Parallel Line Construction; (5)…

This case study evaluated the significance of implementing an enrichment mathematics course during the summer to rising African American ninth graders entitled, "Geometry Honors Preview." In the past, 60 to 70 percent of African American students in this school district had withdrawn from Geometry Honors by the second academic quarter. This study…

Here is the only reference book you will ever need for teaching primary school mathematics and statistics. It is full of exciting and engaging snapshots of excellent classroom practice relevant to "The New Zealand Curriculum" and national mathematics standards. There are many fascinating examples of investigative learning experiences,…