I have used a magnetic wand and magnetic chips in my studio for years. I call them magic notes. The students love to play with them and they are just the right size to represent a note on the staff. We use them for marking cards, note learning and even counting scores.
I used them recently in the Tic Tac Toe Game. I call the wands, Magic Wands and the chips magic notes. Here is a link to a website where you can purchase them.
Another link for Magnetic Wand
Check out these Great Resources!