This is another frequent question. Unfortunately the premise of the question, which is that one learns to be a professional actor by going to college, is wrong. There are a few good college acting programs, and I mention them in my book, The Tao of Acting. However, acting and academia is not a good fit. Most college acting programs are hampered by having to meet academic goals and having objective grading standards. Acting is quite subjective and should not be shackled by academic rules for objective goals. While superior programs exist both in the US and in the UK, the truly talented and experienced high school graduate would do better in a professional school or academy. First of all the program is shorter, usually two years rather that four, and that give the student who graduates from the professional school a two year head start over competition his age. Of course, the gifted and mature student who goes straight from high school into professional acting without going to either kind of school is ahead of students at both. A few have done that, like Heath Ledger and James Dean, for example. \
The problem is that youngsters have been taught that they have to go to college to get anywhere in any field. It simply is not so, especially in acting. The idea that people become actors by going to colleges and or acting schools is so wide spread that every year we are inundated with tens of thousands of graduates for whom there are no jobs. Acting is unlike any other profession. What matters in acting is your look (not necessarily beauty), your talent (which must be extraordinary), your personality (which must be a lot of things pertinent to acting careers), your knowledge of the industry and how to navigate in it so as to get ahead, and LUCK.
While there are some snobs who think it important that an actor study at a particular place, casting is never done on the basis of where someone when to school. It is based on if you look the role and if you can act the role (both of these things superior to the competition).
So school is not the important thing in being an actor. But if you choose a school what you put into it will determine more about what you get out of it than the curriculum will. In my mind the purpose of college for an actor is to give him or her maturity and acting experience. If they happen to make some connections with the profession while they are there, all the better. The better acting schools will have classes in how to become a professional actor and/or a senior showcase for agents and casting directors. Good acting schools are very expensive ($30K a year and up). They are also very selective (Julliard takes fewer than ten new students each year). And they will drop students who do not make sufficient progress. It is very difficult to get into the better schools, stay in them, and graduate. And then it is very difficult for most the their graduates to get a job. (Because there are so few jobs).
The subject question of this post will long be debated with no definite conclusion. How the school fits your needs is more important that the school's reputation. And I must emphasize again that no school can guarantee you an acting job.