When our daughter was 5 years old, we started giving her a little allowance for cleaning up her room to get her used to the idea of money. As soon as she ever got any money she would immediately want to go buy a stuffed animal (this is still true at age 8). One time she had saved up about 5 dollars and wanted to go get a new doll so we went to the store. After looking around for a bit she found one she really liked but it was $10 which was more than she had. We told her that it was too much money and that she needed to buy a smaller one that cost $5. After about 3 seconds of sadness I gave in and said I could pitch in some money for her to buy the stuffed animal (way to give in dad).
She thought for a moment and said, “Hey Daddy, since we are going to split the money for this we can have me buy the head of the bear (it was a teddy bear) and you can buy the behiney!” I guess I still technically own that bears bum to this day!