Take for instance my 15 year old.
He has classes every day at the local college. He gets dropped off, he gets picked up.
While I'm sitting in the car waiting for him, I've observed that college kids, on this particular campus at least, come and go individually. I never see kids in "groups" or even "pairs" for that matter.
Everyone seems to be there to go to classes, not to socialize.
Compare that to the local high school peer dependence, and peer situations, plus the length of time that is spent during the day at class (high school probably 30 hours a week, college 15 hours a week) and this college seems a much better atmosphere for an education.
As far as subjects, I don't think College Algebra, Oceanography, Composition, or Spanish are too controversial. And if they do introduce controversial subjects in certain classes (and I've warned my son that this will probably happen), he can come home and discuss them. His comp teacher assigned three pieces of reading during the first week. One was by Andrew Sullivan and discussed gays in American society, but my husband and I made it a point to read the article as well, and discussed it with our son. (not that the gay lifestyle hasn't been discussed before because some of our neighbors are gay.) Unlike high school, he won't be getting sex ed from an instructor with bias.
His friends are other kids his age that come over to our house to play pool, or neighborhood kids that play football in the park across the street.
Truth be told, I don't want my child to have the normal "college experience". I've had too many friends send their kids off to college, and the normal "college experience" involves drinking themselves into a stupor and having unprotected sex.
I want him to go to college for an education, not for an experience.