Schoolwork aside, think very carefully about who you befriend and whether or not they will end up being an absolute jerk. I know a guy who is such an asshat that he left two of my good friends alone in his own house with my other friend, drunk out of his mind and sick as hell, just so he could go to the park and get high. Don't associate with those kinds of people and you'll be golden. Oh, and develop a good work ethic. Study, do a thorough job on homework, focus on assignments... it's a little hypocritical of myself to suggest that, BUT GET THAT MINDSET DOWN AS EARLY AS POSSIBLE; you'll save yourself a lot of headaches and possibly even money later on.