We already know kids are crafty...
So, why not put it to use and work on some fun, beautiful projects?
Write a love letter in invisible ink for Valentine's Day (hint: all you have to use is lemon juice).
Create instruments out of cardboard.
Do some simple origami.
Roll up some paper beads.
Paint with ice cubes.
Or just check out this site, and find something that appeals to the kiddos (the parents won't be able to resist).
The best part about the site is that these crafts are so easy, so fun, and so cheap.