A dodecahedron is a three-dimensional figure with 12 faces. The Greek prefix dodeca- means 2 + 10.

The dodecahedron in the picture has 12 5-sided (pentagonal) faces. That's why Dodecahedron Day is on December 5 each year.

Click here to see students celebrating Dodecahedron Day 2004.

The most fun way to celebrate Dodecahedron Day is to build your own dodecahedron! Click on a picture below to learn how to build it. Ask your teacher if you need help.

Teachers may follow the "Resources" link below for classroom ideas.