Remove the compulsory nature of education, and 90% of the problems will be removed. The students that cause most of the disruption problems will go disrupting elsewhere, but at least they won't get in the way of your child's future success anymore. Most of the administrative problems will be removed when the unions and politicians are shown the door. Most of the remaining problems will disappear when competent faculties are allowed to remove incompetent emloyees.
Also, you might want to check out this thread, where Educational Leadership magazine openly admits that they are focused on turning students into social activists.