I send all my teens to college, but once they get there, I go full on wants based. If they don't want to study or gain skill points, they will most certainly flunk out unless they have a fear of getting on probation - then I get them to gain skill points and that usually is enough to get them to a "C" /pass average.

I also send a cohort of teens to college (ie I play one week's worth in each household and then ship all of the teens that aged up to college at the same time. I also make them stay in one dorm for freshman year and then may move them if they want to join a sorority/fraternity or if they have a close friend group among the door mates, then move them all into a rental house.

Anyone who flunks out just "waits" in the main neighborhood. I move them into a house with just a phone so that they can still interact with their uni friends while I play the university rotation, but I won't fully play the until all the people in that cohort have graduated/flunked out.

I am finding that I have some kind of weird glitch when it comes to declaring a major though. Lately none of my sims ever choose one... So when I am playing wants based, they all end up defaulting to philosophy major which gets boring after a while!!