When you run errands with your child, assign him the task of counting the change you receive. This will give him the opportunity to apply the skills he's learning in school while also ensuring that you receive the correct amount of change from each cashier. As an extension activity, save your receipts and make a game of playing cashier together at home. Pretend that you're making the purchase, pay with pretend money, and let your child determine the amount of change you should receive.