I used to sell printing and many of our clients were carrollton/FB ISD teachers. After dealing with them for a year I decided that my kid wil not go to public school. I found the average public school teachers to be some of the most vial, biased, opinionated activist assholes I've ever encountered. Almost every one I dealt with had either some weird religious angle that they'd try and subversly push on the kids or an equally weird world view. I got the impression that the majority of them felt like they were on some mission, not just to teach the curriculum but to mold young minds into smaller versions of themselves. It's an ego trip, nothing else.
Looking back at my experiences in school we had the same thing going on, only I was too naive to realize it. My parents would have probably been livid if I told them all the crazy shit that some of my teachers told us. I know I would be.