I don't use a chart but I use a bucket. It's what his Kindergarten class uses. When he does something good, I put a ticket in the bucket. When he fills the bucket up to a certain line, then he gets a prize. I bought a bunch of stuff from the dollar section at target.
Oh and it works amazingly well. And I never take tickets out of the bucket for bad behavior. I will just tell him that he isn't going to get a ticket for that kind of behavior and it really upsets him. His behavior has really improved. He looks forward to getting a ticket in the bucket so much and feels disappointed when he doesn't.