>The teacher-student-parent relationship isn't adversarial.

Sometimes it is, and in those cases parents need to advocate for their children. The unfortunate truth is that there are asshats in every segment of the population, including teachers and school administrators. Parents need to be prepared to defend their children in case they end up with an asshat for a teacher or principal.

I lived in Germany through the fifth grade, and attended German public schools through the fourth grade. My fourth grade teacher hated me because I was American. This is not a guess, she literally told me on the first day of school that, unlike all of the other children, I would not be given the benefit of the doubt but would rather have to "prove myself" because I was American. She also regularly made negative or disparaging comments about Americans in general. Based on her age, she must have been in elementary school herself during WWII, and I'm guessing she had some bad experiences. My parents literally had to have an adversarial relationship with her for my sake, and ended up pulling me out of the German public school system at the end of the year and putting me into a joint German-American school because she would have been my homeroom teacher again the next year (we kept the same teachers for three-year blocks: one set for grades 1-3, another for grades 4-6).

When we moved back to the states, they ended up needing to adopt an adversarial relationship with the principal at my new elementary school. As the "new kid," the top bully had singled me out for special attention. Any time we had an encounter, no matter how one-sided, the principal would dish out equal punishment to both of us because he was too lazy to figure out the difference between "two boys fighting on a schoolyard," and "one boy punching another boy in the back of the head repeatedly without warning or provocation." Fortunately, the principal was also stupid and craven. After he suspended both of us one day for an incident where I had not even tried to fight back, I called my parents from the phone in the school library (it was an in-school suspension) and told them what happened. They promptly called him and asked him to explain the situation. He told them a bald-faced lie about what had occurred, then called me into his office and yelled at me for daring to call my parents. Fortunately, my parents hadn't bought his story and had left the house immediately after getting off the phone with him. We lived close enough to the school that they walked into his office while he was still screaming at me at the top of his lungs. My father had been home that day so he had come to the school with my mother, and I'm still not sure how my mother kept him from beating that man, but she did. I was sent back to the library, and after about fifteen minutes I was told my suspension had been rescinded and I went back to class. After that the principal never looked me in the eye again. My parents had a series of meetings with the school board and various people at the school district, and at the end of the school year the principal was "promoted" to a dead-end administrative job at the superintendent's office. I don't know the details of what they worked out, but some of the shit he said while yelling at me was completely inexcusable and would not have looked good at all on the front page of the newspaper.