If you have a lot of coins you can just put them in those things that give you cash or exchange it at the bank.
Depending what state you live in you could get the refunds off of plastic and glass bottles.
Ask pretty much everyone in your school if you can have a dollar. People usually dont mind just giving one dollar away. After 20 people, you'll have $20. If that doesnt work, ask 40 people for 50 cents or 80 people for a quarter. It takes a while but this stuff works.
Trust me, I'm a broke bitch and I have had tons of experience with this stuff. $20 is not that hard to
come up with.
