if you want good grades get to know your TAs. most courses are run more by the TA not the professor. Trust me, i bump the grades of a few of my students because of the extra effort they put in with me.
if you want to go to grad school / get a job get to know your professors. networking is a huge part of being a professor. they'll have a lot of contacts at other schools and industry that can go a really long way to launching your post college career.
don't forget to have fun. school is important but you should have plenty of time for other activities if you manage your time well. join something, anything really. make some friends, drink a bit, get to know people you wouldn't otherwise talk to. the experience is just as important as the grades and diploma.
...and don't pittle the dittle of the little boys.
