Teach him responsible financial behavior. I would definitely start my kids with using plain simple green cash. Let them feel and see the cash. No cards, no checks, no speed pass! All cash. It seems that young kids don't fully grasp where the cash is coming from and they believe it is endless. Teach him how to earn that green stuff, how to save it in his personal account, how to create and stick to a budget, and how to withdraw the money when he needs it. Teach him the benefits of compound interest and the downfall of getting into debt. Being able to get in debt to "build credit" can come later. Good Luck!