A quick and simple math craft that I saw in the last Family Fun issue and that M and I did a few days ago. I couldn't think of what else to do that day after a successful crayon-melting experiment (trying to see what would happen when a spaceship (crayon) flies too close to the Sun (our oven)).
Fortunately, I had 20 small paper plates that were taking up valuable shelf space in my kitchen for the last couple of years. M got to use the stapler, so he loved it. He also made an observation ('cause you know, astronauts observe and experiment) that the resulting polyhedron looked somewhat like a ball. Except it had lots of surfaces and edges (new words!) and wouldn't bounce.