Peanut Butter Scoops
Every child I have ever known loves to eat peanut butter right off a spoon. Why not prepackage peanut butter on colorful, disposable plastic spoons (or scoops)? Packaging could easily be done with all the current trendy logos used by other 'kids' products (i.e. Disney characters, etc). Spoons could be made collectable by associating them with sports figures, etc.
Reward: knowing that this is a good idea!