American public schools are not bad. The problem is the range is so wide. Schools are financed for the most part by local property taxes. More affluent towns have extraordinary schools. I had a private school picked for my future children. Education is so impt to me that I would not have children until I could afford the private school. Tuition is higher than college tuition. NYC has specialized high schools. These schools are more diverse, much better academically and socially, and free. The competition is brutal, however. The kids know their parents are Manhattanites. No one wants to move to NJ.
Inner city schools don't have enough funding and the teachers are basically out to lunch. Children fall further behind their peers with each grade they pass. My junior class was given a surprise 5th grade arithmetic test. I finished it in 3 minutes and returned. My classmates had tears. I knew these kids from the Witnesses and around town. They were bright. 75% of my class failed. They had to take a special course to graduate. The catch was that knowing the teachers, those kids would still not be able to pass a fifth grade arithmetic test. I begged for my test back to proof it.
In English class in the college track, if you knew the name of one character in a novel, you received an A. The teacher agreed I could do leadership tasks rather than sit in class and cry from boredom. Not much has changed. I learned many things until the racial demagraphics were too skewed for the times. They said at the time that parents make the difference.