It was actually mostly to do with school size. Once they got the high school down to the much smaller size they thought would be ideal, students no longer were

It was actually mostly to do with school size. Once they got the high school down to the much smaller size they thought would be ideal, students no longer were able to participate in any of the classes or extracurriculars they wanted. So most of the students quickly came to hate school, became completely checked out, and eventually just dropped out entirely. He still hasn't paid any sort of reparations to these students, despite completely destroying their lifetime employment prospects by using them as a science experiment to stroke his own ego.