Let's Face It

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Students will be able to identify the five regular polyhedra (tetrahedron, hexahedron, octahedron, dodecahedron and icosahedron) and describe basic characteristics about each.

Overview of the Lesson

Students are introduced to the idea of three-dimensional figures by first reviewing polygons and regular tessellations. Comparisons are made between regular tessellations and five special polyhedra. These polyhedra, known as the Platonic Solids are the tetrahedron, hexahedron, octahedron, dodecahedron and the icosahedron. Students are provided with the necessary materials to construct these shapes. However, they must decide how to build them on their own. Using nets as blueprints, students construct the polyhedra and record the number of faces, edges and vertices for each. Finally, they are asked to look for a relationship between the number of faces, edges and vertices, (Eulerís formula).