If you child is over the age of 12, they are old enough to be exposed to your finances and information. They learn how to manage their money by watching you manage yours then doing it themselves. Teach your child be responsible for paying the bills every month (with supervision) and balancing your checking account. This is eye opening for a child, because they start to learn the cost of living (rent, mortgage, food, car, gas, electricity, student loans, etc.)