# Teach Math With Fun 3-D Shapes

The Skills it Builds:
Geometry
Spatial Reasoning
Manual Dexterity

To make geometry come alive for your kids, grab some pipe cleaners and straws and start shaping up.

Sometimes the simplest projects can demonstrate the most profound ideas. Using humble materials to build a 3-D shape, kids can begin to understand how the things around them -- from soccer balls to supermarkets -- are made of forms mathematicians call polyhedra (Greek for "many faces").

With sturdy scissors or nail clippers, cut pipe cleaners into 3-inch and 6-inch lengths. Fashion a connector by bending a shorter piece around the center of a longer one, as shown below.

#### Start Building

Slip straws over the folded prongs to create a basic two-dimensional shape such as a triangle, square, or pentagon. Using the connectors' other prongs, add faces in the same shape. Here are two polyhedra to try.

1. Cube - Use the connectors to create a structure with six square faces. To up the cool factor, angle the corners to make a rhombohedron.
2. Dodecahedron - Cut straws into 4-inch segments. Use these segments and the connectors to create a structure with 12 pentagonal faces.