College professors will probably be very different from your high school teachers. Part of this is because college classes are different from high school classes; part of it is because they have a lot more freedom; and part of it remains a mystery.
First of all, with classes ranging from 15 all the way up to 400 or 500 students, your professor may not be able to devote individual time to you like your high school teachers did. In the larger classes, they don’t usually learn your name unless you raise your hand a lot in class or make an effort to get to know the professor in office hours. They are also much less likely to work their schedule around you—meaning you can’t take a final early so you can go on a vacation—but some still will try to help you out when they can.
That’s another thing—if you have a question or need help, you usually can’t just hang around after class like you did in high school. You will probably have to either make an appointment with your professor, meet him or her during office hours (a time professors allow students to come discuss class or whatever else with them), or email them and hope they get back to you.
My advice? Go to office hours! Professors are more likely to remember your name—and help you out with questions or problems—if they can see that you are making an effort.
Just because professors are busy doesn’t mean they won’t be willing to help. You’ll probably get a couple grumpy old tenured professors (tenure basically means they can’t be fired) who don’t really want to be teaching, but you’ll also get some who are very passionate about what they do. A lot of professors really care about how their students are doing, and want to help them. (Find out what students think of the professors at your school at www.ratemyprofessors.com).
One more thing that can be a little different—you won’t always have a professor teaching you. Some classes have a big lecture taught by the professor, as well as smaller meetings (like labs, discussions, or sections) taught or led by a TA, who are often graduate students.
Personally, I think the best part is that you finally get a voice. At the end of the course, you will get to anonymously review your professor. So if you like him/her, you can give out praise, and if he/she was an unfair grader, a bad lecturer, or incapable of ending class on time, you get to share your opinion on that, too.