I picked up a bunch of stuff from school that would perhaps have never fully developed if I hadn't gone there, or if I'd had my own choice of exactly what to do. I would never have chosen to take a history class, and yet in that class I learned critical thinking skills in a way that I would have had no direct cause to do outside of that environment. I gained a basic grounding in science. I learned enough about a variety of different subjects that I was able to make an informed choice on a career path.
I certainly believe that the school system needs changing, particularly as self-learning becomes easier, and I agree that kids need more responsibility (I recall aching for it in my teenage years), but the number of comments here suggesting that school is of no use whatsoever surprises me.