On Amazon right now you can get this adorable Cool Backpack Flower Coin Bag, Wallet, Hand Pouch Purse for just $2.05! Plus it ships free. I think this would be great for kids to keep change, lip balm and other small items contained in their backpacks.
Note: Amazon prices and promotions can change at any time. The price(s) listed in this post is/are subject to change.