Do what I'm doing. Every single quarter, penny, nickel, dime, collect it in a piggy back. It all adds up since its money! As of this moment, I have a piggy bank and a sack of change that will probably add up to 25-35 dollars. Plus, I have 28 dollars from my birthday! I find that putting your dollar bills in the piggy bank saves you from impulse buying.
However, you can only do this if you have a Coin Star somewhere in a grocery store like Publix. They are basically big machines that you dump your change into and it counts it, giving you a receipt. You take that to a cashier and they give you the money(: