In high school they told us: There will be no grades in a class except the midterm and the final, so you have to study hard because failing one test means you fail the class.
Once I was in college a professor said: Hey, you guys are working really hard on your third paper, so I'm just going to cancel the final and give everyone a hundred on it.
In high school they told us: In college, class always begins exactly at the scheduled start time. If your class is at 9 AM and you get there at 9:01, the doors will be locked and you'll be out of luck, especially if it's the day of the midterm or final, because then you get a zero.
Once I was in college a professor said: Does anyone mind if I start class at 3:35 instead of 3:30? These elevators are really slow and I want to have time for a cigarette before I teach for 90 minutes.
In high school they told us: Every class you miss drops you a full letter grade in college courses.
Once I was in college almost every professor said: You can miss three classes without a penalty, and a few more if you have a Doctor's note. Sorry to be a hardass, but you automatically fail if you miss more than ten days of class.
In high school they told us: If you do have papers, your professors just lecture and put the assignments on the syllabus. You're completely responsible for remembering the deadlines, they won't remind you. All your professors will do is lecture and the rest is up to you.
Once I was in college a professor said: Okay, so your next paper is in two weeks! I'll keep reminding you in the interim, but I just want to make sure you have enough time to do it! Let's run through the structure I want to see real quick, and if you have any questions, feel free to email me or come to my office hours!
In high school they told us: You have to use MLA formatting and if you make any mistakes in your citations, it'll be considered plagiarism. You'll be expelled and probably sued.
Once I was in college almost every professor said: Please do not use MLA, it is awful, we use either APA or Chicago here because we are not 14 years old.
Stuff changes: Be flexible.
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In university I had professors who stood at the classroom door to lock it at the exact starting time. (jerk)
I also had professors who if one arrived late, welcomed you to
class and brought you up to date on discussions.
I had one memorable professor who was an alcoholic and was incoherent after noon. Everyone loved him and learned to take early classes only.
Does college prepare you for "real" life? You bet your ass it does!