I certainly won't be the first to say it, but college is a bit of a bubble. Not like a soap bubble, more like one of those edible bubbles you can get at quirky gift shops sometimes. This bubble won't pop, even if you put it down on a table. In high school, your parents took care of your food/housing/discipline. Well, no, the bubble will pop. In four years. So it's a soap bubble. A four-year one. The point is that it's like practice for real adult life, the first time you're really taking care of yourself. Oh, but the bubble pops slowly. Yeah. Like John mentioned, it's sort of fun and cute to get irresponsibly drunk and maybe break the law early on in college. The consequences are often solved with a little carpet cleaner and the stories are great mementos of wild-oat sowing. Unfortunately for me, my wild days in college involved actual wild-oat sowing, as in plowing and sowing wild oat seed in north fields. Good stories, though. I was down on my knees, digging deep and burying those oat seeds, with the hope that maybe half of them will survive the harsh winter on the plains. God forbid there's a fire before the harvest!
Anyway, you get older and maybe you realize that stealing street signs is in fact stealing, and people who steal things end up in jail with alarming frequency (there's a Nightline piece for ya, Ted Koppel). The number of laughs you get per misdemeanor decreases. You realize your need to have a protective 'college shell' around you is gone. But this pseudo-adulthood is still useful. The costs and risks involved with doing something new are lessened, so you can be less tenuous in trying something you might not have before. Last night, some friends of mine told me they were going to a swing dance in Wilder and that it was open to anyone. I told them I had never done swing dance before, and wondered just how embarrassing the whole ordeal would be. They told me about the beginner's lessons before the real dancing started, and that everyone there was super happy to have new people join. Also, there's usually a much larger number of females than males. Moral support and a favorable guy-to-girl ratio pushed me over the edge and into my first swing dancing adventure. It was great, as it turns out. I learned basic steps from my friends Joanna, Eric, and Annika, and unbuttoned my shirt to the third button to look like I wasn't taking the thing too seriously.
So the trick is this: learn not to do so many risky, stupid things that could get you in trouble with the law over the course of your tenure in college, but learn to do slightly less risky, fun things that could make you new friends or just sate your curiosity while these things are cheap and you don't have children.
How are academics different in college? I think one major difference is that teachers in high school are really happy to have students who act like I did, and like I imagine you did. They are just thankful to be teaching students who really want to be in class most of the time. When you turn in a paper or do a project, teachers give grades based on whether you got everything 'right.' Basic stuff like spelling, grammar, and punctuation, but also just making sense and sounding like a grown-up in your writing. Whether or not your ideas were good or whether you argued for something new and original doesn't really come into the equation much. Assignments in high school are more like practice. If you can find a teacher who does push for more original ideas, you might not know how lucky you are until much later.
Once in college, more is expected of you. This is one of the main changes when you move on to college, in my opinion. It's not that you are much older and more responsible, but you are expected to be. You have your own living space and health to take care of, and since you are paying to go to school, it is basically assumed that you want to be here. Professors are here because they want to edify excited educatees. When you turn in papers and other assignments in college, implicit in the grading is the expectation that you did some real thinking about the ideas surrounding the topic, and came up with something unique to say about the book/film/research project. While you may not be ready for real life yet, college is not practice like high school is practice.
Also, if you choose to pass along any of this 'wisdom' to anyone, find a better metaphor than a bubble. It's trite and not very good to begin with. The same thing goes for 'wild oats.'