At one of my old high-schools, you didn't even have to attend the class. They wanted you to be responsible for your own future. It was sort of set-up like a college.
Of course, I wasn't responsible. I was like "AWESOME I DON'T HAVE TO ATTEND CLASSES HELLZ YEAH". Eventually I dropped out of that school.
Now I'm 18 and still haven't completed high-school. I still have a year and a half to go.