Things to do in or around NW New Jersey during Spring Break?

Hi everyone. Well, here goes my sad, sad story... I am a junior in high school and I'm going to turn 18 before spring break rolls around on the first week of April. My friends and I were planning to go to Florida (Ft. Lauderdale if possible) for our spring break because it would be tons of fun - however, the pricing, the age restrictions and everything else just totally killed our mood and drive to go. We still want to do something really fun (possibly sleep away from home xP) and I wanted to know if there were anything pretty cheap ($200-400) to do for a few days in or around NE New Jersey. Please help!!! For example: train trips? camping?