You’re only detailing the failure of the liberals to bring about improvement in the lot of a people group that they have subjected to the soft bigotry of low expectations.
The "Stand and Deliver" movie was an example of what can be accomplished when expectations are kept high and both students and teachers make an effort to achieve success. You don't get that kind of result in classrooms full of feral thugs who don't want to be in the room. Decent students and teachers flee from those environments.