When I was in college in 1970, I had a Differential Equations "teacher". I don't remember his name, but he was so tall he had to duck in the door frame to enter the room. He was also red-headed. Being young, introverted, and naive, I didn't speak up much. But this so-called teacher talked so much about how bad it was that we were in VietNam that we rarely had a real lesson in DE. I got a B in the course, but didn't learn anything. Now I'm an engineer, and it was quite difficult to solve certain problems; I had to do substantial self-study to make up for what I paid for and didn't get.
I see this so common in grade school and high school today. My two kids came home and told me things, not about their lessons, but about their teachers' points of view on current events.
It's no wonder our population leans toward the liberal. The kids are being taught - not their supposed lessons, but politics - they're brainwashed every day in school. I think that may be one reason that we have so much teenage rebellion these days.