They are not required to go to college but they may not go straight from high school to the NFL. That has a lot to do with the physical nature of football. Those "helmet knockers" are responsible for millions of dollars coming into the school.
I'm really not trying to crap on the players but I know I'm being condescending. But baseball sends the younguns to minor leagues. And you'd be suprised to see how many Athletic programs ate operating in the red.
But in order to get these guys through who hardly meet educational minimums schools play academic gymnastics, I used to crack up reading their papers, them being absent every Friday class, and never having to take notes because we are to provide them with notes and studyguides closely modeled after the tests. Their told they don't apply to the rules and Suprise, they act like that outside of the classroom.