Our hunting retriever club has a "Junior Handler" event, it's the cutest thing you ever saw, the little itty-bitties, some 3 or 4 years old, out there handling a big high-powered Lab or Chessie (of course the Lab has an eye on the owner/handler, who stands right behind, but a Lab will work for anybody. All I have to do with my older dog is point and say, "Go with [fill in name here]" and she will work her heart out for them.)
One of our junior members (isn't she adorable?)