Here are a couple of printable math centers made available thanks to Mathwire. Both a useful for giving students practice with shapes as an introduction to geometry.
The first is a called a Polygon Quilt Game. Students pair up, and each person picks one color to use in the quilt game. They take turns coloring sections of the picture, one small triangle at a time. The goal is to try to create larger shapes with their color. After the quilt is completely colored in, students tabulate the points they earned based on the shapes they were able to create. The more complex shapes are awarded more points. Students will have to strategize to win this game. Here is another site that explains the rules.
The second activity is similar, called Spider Web Map Coloring. 3-4 players play this game, and they have to use a labeled die that tells them how many spaces to color. They can only color sections that do not share a side with one they've already colored (but the sections may share a corner).
A second version of the Spider Web Map is in the same file. The same rules apply, except each section has a number assigned to it. That number is the amount of points awarded for coloring that section, so students will have to add those numbers at the end to see their final score.