Origami

For more on the art of paper folding, check out the Origami Resource Centre. In particular, this site provides a variation on the Columbus Cubes exercise using business cards.

David Mitchell's book Mathematical Origami was the source of the Columbus Cubes exercise described elsewhere on this site. Although most of it's examples are probably beyond the capabilities of the average 10 year old, the more precise, mathematically inclined paper folder will find some neat models therein.