When our son (now 20) was 3 years old, we started giving him 4 quarters a week as an allowance. He was allowed to spend 2 of them and required was to save 2 of them. When he had accumulated $10 in savings, he was allowed to spend that too. The immediate spending part eliminated potential tantrums, as we were always able to say, "Certainly you can buy that. Do you have enough money?" The saving part demonstrated that he could buy more expensive items if he was diligent about savings.