If you are an idiot, it's better to recieve an idiot- appropriate education. Less calculus and Shakespeare and more how to get a steady job, handle your finances, and stay away from trouble.

It would of course suck if you just had a cold on the day of the rest and wound up in the idiot school by accident, you'd need to review performance regularly. Ideally you'd have more than three levels of schooling. Maybe five, you could label them alpha through epsilon.