The rigging of our system begins before a child can properly read or write. One of the striking aspects of policial correctness, though one not thought about frequently, is that a teacher can with impunity teach that which is politically correct, and will certainly be vulnerable teaching that which is politically incorrect. The proper work of a teacher is to present different interpretations without judgement or preference, but the practice seems to be heavily in favour of cosmopolitan thought. Children are not asked to consider what is good or bad about diversity, they are instructed to celebrate it. Children are not asked to consider what is good or bad about BLM, they are instructed to create displays supporting it. Children are given books about whites being bad to blacks (that's fine) but no books about blacks being bad to whites (that's racist). From the youngest age, the child is indoctrinated with the desirability of diversity and immigration, and an unquestioning acceptance of white guilt and black victimhood.
For the supporter of diversity, school exists precisely to monopolise the child's mind in this way. It is indeed one of the striking indicators of diversity's oppressiveness and incompatibility with the liberal democratic mindset.