hahah what an old thread.
this year is my senior year, i want to try to get something very large, like a huge derelict boat or horse trailer or motor home or something, paint "SEN10RS" on the side, then tow it to the middle of the busloop at the school, take the wheels off, and leave it there.  it would be the first thing everyone saw in the morning when they came to school, and when the school found out who did it and made me move the thing, i would just throw the wheels back on and tow it away. no harm done to anything.