Fundraising ideas for Study Abroad Program...?

I am going to Costa Rica next summer for a Study Abroad program. I need to raise about $3500 for the trip. I have a summer job lined up but that money has to go to pay for my rent, food, and gas. I have also looked at scholarships and I can get one that is up to $1000 through the school, but that still leaves about $2500 to raise. Please help...