Reward Systems

So I've been looking at Reward Systems. I've been using Candy for Potty Training. Actually, I'm going to pop the candy out in the open now, in a gumball machine and use that as even more motivation to go potty. But I have recently been pondering the introduction of rewards for good behavior and chores. (Of course it would be chores my son could handle.) I've see several star charts or happy face charts. I think that will work for now. But as he gets older I've wondered if he'll remain as excited about putting stickers on a chart. I've also recently come across these Happy Tickets from Ambrosia Girl. She has them available to download on her blog. Cute as can be, and I can see them being more effective once the kids are older.