For me it wasn't Sophomore year. It was my Junior year before I really got the hang of going to school and balancing my time. Since then, I think I have had a 4.0 GPA. That sort of thing leads me to believe it isn't so much about being their long enough to get used to it nearly as much as it is taking the time to come to the conscious conclusion that you haven't been setting your priorities right. My wife likes to think that this means always doing your work and making sure that you're completely done with everything before you have any fun or relax at all, but that isn't necessarily the case. Relaxation and relieving stress should be on your priority list as well. You function best when your life has balance. It's about trying new techniques of time management until you come to that balance.
That's all probably more than you wanted. What I'm really trying to say is that if you are working at getting the college thing right, then before too long you'll have it down. I firmly believe that most people intelligent enough to get into college are smart enough to navigate their way through it. I don't imagine you're any different.
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"It is the wrong question to ask, and therefore, as one might expect, has
no right answer." - Hans von Campenhausen
This is the philosophy of my life.