I think I first learned to make these at camp when I was a kid. They make a great summer project and are always a nice gift for a grandparent.
Here's what you'll need:

• A couple of sticks about 12" long and 1/4" in diameter.
• Yarn, all different colors.
• Scissors

Tie the two sticks together in a cross with a piece of yarn.
Take a turn on one stick then go to the next keeping the yarn tight to the middle and the cross square.
Keep doing this for a few times around then change the color of the yarn.
Repeat this until you have filled up the crossed sticks with yarn.
Tie a piece of yarn on the end of one of the crosses so your art can be hung.

Be creative and have fun. Make one for your parents while you are at it.