As many of you are in the midst of taking AP exams this week and last, I want to make something clear: do your best, but please don't stress. Grades, ACT or SAT scores, extracurriculars and essays are much more important than APs because typically AP scores don't go on your college application. They don't count towards your GPA, and they're not part of your transcript. There isn't even actually a place on your application that they're required.
So, the question is, do admissions committees even look at your scores, and how much do they actually matter? The answer is if you self-report, they will look at your scores, and how much that matters is probably none at all. AP scores affect the classes you take in college once you're admitted. You can place in certain higher-level classes or, even better, skip classes if you score a 4 or a 5 when you're taking an AP exam in a certain subject.
There is a place on most college applications, the common app, where you have the option to report these scores yourself. This process is called self-reporting. So yes, colleges appreciate when you self-report your scores if your scores are excellent. Think a 5, which shows that you have prowess in that discipline.
Remember, self-reporting AP scores is optional. Yes, you can send them via college board for a fee. But if you have scores that are unimpressive, they could just as easily count against you in a very competitive college admissions process. So, given the choice between two similar candidates, an admissions committee is probably more likely going to select the one who submits high scores or none at all rather than the student who submits not-so-good ones. Think 3 or below.
In general, though, you should not consider AP scores as a make-it-or-break-it factor in your admissions process. It's not. Just be proud of yourself for taking the class and doing your best.