I've seen that episode (Princess and Buddy pretty much only watch Disney channel). The one little boy wins the science fair and gets 10 coins, but he wants to buy a toaster that costs 15 coins. He and his friends realize that if he saves his 10 coins and waits until his birthday when he usually gets 5 coins from his family, then he'll be able to buy the super duper toaster that he wants. Then they go through a bunch of different ideas of where he can save the money, until finally they wind up at the bank. It is cute, and it does reinforce the idea of saving.
Interestingly, I originally learned personal finance via comic books as a young kid. I believe The Fed still publishes them for free.