We've been doing something in our house for about six months now. We have created a small treasure box. In an effort to have our kids focus on good behavior, we talk from time to time about the blessings that God gives us. How he loves to reward his children. In the same way, every so often my husband goes to the dollar store and picks up various items to replenish the box. He loves doing this and would be disappointed if I showed interest in doing it for him.
When he comes home from the store, he shows them all of the things that will be added to the box. It builds some excitement when he does this. When we notice them working extra hard in school, showing integrity or kindness, or just in general having good attitudes, they get to choose something from the box. It is filled with fun pencils, little notbooks, some small candy, mints and bubbles and new head phones for their MP3 players. (As a sidenote, I love those MP3's. The older ones can listen to stories on them or worship music as they go to sleep and it doesn't bother the younger ones who aren't old enough to have them yet or go to bed sooner.)
There is nothing that my husband likes to do more than to lavish on his kids. I think the same is true for our Father in heaven. I think it's a great example of that relationship.