I did that for my high school graduation a while ago. They shut down the park and just let in seniors from various schools and go from sunset until early in the morning. It was a long busride then, too, but fun.
The teachers searched our luggage "to make sure we brought a lot of sunscreen." My lit teacher was the one who went through my bag, and was intrigued to find I brought a couple of books for the ride down. Yeah, I was dull.