This doesn't make sense.

Ah, the paradox of high school. It sucks. And you can't leave unless you are really really bad.
School just is not enjoyable, overall. And isn't it ironic that the good kids, who probably are done learning from it and have no need to be there are stuck going until it's all "done." However, the misbehaving, unkind, law-disregarding kids get the opportunity to not come to school for periods of time. What the heck? So, you are rewarded for misbehavior and punished for kindness and intelligence. What is the deal?
"HEY! You're smart! Sit here for 7 hours everyday!"
"HEY! You! YES YOU! You did something stupid--you don't have to come to school anymore!"