This lesson from Illuminations focuses on quadrilaterals. Students will start with the diagonals of a shape and then deduce the type of quadrilateral that surrounds them. An interactive applet is included that will help...

Discrete Mathematics and Theoretical Computer Science (DMTCS) is a peer-reviewed electronic journal "devoted to rapid publication of innovative research which covers the fields of Discrete Mathematics and Theoretical...

This lesson from Illuminations asks students to construct perpendicular bisectors, find circumcenters, calculate area, and use proportions to solve a real-world problem. Concepts taught in the lesson include...

An investigation of the formulas of the surface area and volume for the dodecahedron. With icosahedron extensions.

A unit designed to improve students' understanding and appreciation of basic geometric shapes used in architecture. It describes various plane geometric figures and discusses in detail the properties of several of these...