Players on son's team were "vetted" pretty well with several pre-reads and character "checks" (staying on campus several times). This was at a high academic school.
That being said, several players were "off the team" for other reasons: One may have been "having too much fun", but it was his lack of judgement by hitting a police officer (and subsequent overnight or two in jail) that got him kicked off the team. Another got arrested for a stupid stunt...off the team for the season.
Lack of grades were not an issue. There is an NCAA GPA eligibility minimum, and the school had their higher minimum. It was the one thing I told keewartson when he went off to school: I don't care about a high GPA, just stay eligible!
However, he had some friends go to a larger school and partied it up pretty well. They both graduated on time, but were off the team after their freshman year. Did their partying contribute to their "non performance" or lack of playing time? Who knows.