Finger Knitting - Taught the campers to do this at summer camp this year. It was a huge hit and a perfect filler for the early finishers. Use a pencil to save their place so they can go back to it at a later time.
Finger knitting! This was fun and really fast (since I'm used to normal knitting) and it made a cute, really thin scarf. I actually made mine really long so I could double the thickness and then I turned it into an infinity scarf. Not bad :)