Welcome back ladies and gentlemen of the internet. Public school systems play a major role in the education of a child, not solely formal education about equations or English literature, but it also formulates for the child ideas about the world they live in, socially and culturally. Though a parent may try frivolously to instill certain values in their child, the child will always have such a strong part of their upbringing and influence come from their school days. Interacting with other children, relationships with their teachers, they're learning a lot more about life than just Christopher Columbus. It's important as a parent to always be aware of what your child goes through at school, and what kinds of lessons are being pushed on them without realizing it.
This brings us to the Reddit thread. In this story, the original poster (OP) is a woman whose daughter gets detention out of nowhere. The teacher confesses the whole story: a boy in one of her groups starts slandering the teacher, although he doesn't know she's watching the whole time. One kid chimes in, while OP's daughter sits quietly. And she's getting detention for that. Listen, it's never a kid's responsibility to protect the adult.