Mathigon
Mathigon: Mathematical Treasure Hunt
The mathematical treasure hunt allows students to follow a trail of clues and mathematical problems around the school site; each clue contains a hint to where the next clue is hidden.
CK-12 Foundation
Ck 12: Geometry: Polyhedra Study Guide
[Free Registration/Login may be required to access all resource tools.] This study guide reviews how to classify polyhedra, Euler's formula, and regular polyhedra.
Mathigon
Mathigon: Geometry: Polygons and Polyhedra: Platonic Solids
A Platonic solid is a polyhedron made up of only one kind of regular polygon, that looks the same from every direction. (In other words, the same number of faces meet at every vertex.) There are only five different Platonic solids:...
Alabama Learning Exchange
Alex: Platonic Solids Ornaments
This is a hands-on activity that introduces students to the five Platonic solids. Students will discover the special relationship between faces, vertices, and edges. Students will research the Platonic solids and then construct and...
Wolfram Research
Wolfram Science World: Pythagoras of Samos (Ca. 560 Ca. 480 Bc)
This site from ScienceWorld provides a short, informative description of many of the contributions of Pythagoras to mathematics. Links exist to some of the contributions as well as to additional information.
National Council of Teachers of Mathematics
The Math Forum: Ask Dr. Math: Polyhedra Classification
This question and answer site provides a lot of basic information about polyhedra. The five regular polyhedra, "The Platonic Solids," are described.
Other
Platonic Realms: The Irrationality of the Square Root of Two
An informative resource on the nature of Platonic Solids and what constitutes these figures.
Other
Polyhedra: The Five Platonic Solids
A brief site that includes some activities to understand the figures.
Math Is Fun
Math Is Fun: Making 3 D Solids
This tutorial features templates and instructions to make the following solids: tetrahedron, cube, octahedron, dodecahedron, and icosahedron.
National Council of Teachers of Mathematics
The Math Forum: Pictures of Icosahedrons
This site from Dr. Math and the Math Forum provides several links to pictures of icosahedrons. The information is somewhat brief, but worth checking out for a background on the subject.