Talk to some local music stores and repair shops. Maybe they have something just laying around collecting dust that they would be willing to donate to your school, or give to you. Just explain your situation and lay on the pity. I'm sure that there are programs around, but I haven't been able to locate anything online. Just ask around, smile, and be cute! No shop owner can say no to a 16 year old girl with a cute smile :)! Good luck!