The main problem with American education is that we have made a certification or degree from a college of education, rather than a degree in a relevant subject, the sole criterion for fitness to teach in a K-12 school. Everyone remembers the general impression of ed majors at their college — by and large a mass of math-phobic ditzes who chose the major because it was the most content-free major at their university (I estimate about 15% of ed majors don’t fit that description, but it’s too few to take up the slack) — who are then given “education” in such baleful pedagogical enthusiasms as look-say reading instruction, Vygotsky’s social construction of knowledge, and whatever the latest iteration of the see-saw between rote learning of arithmetic without understanding and discovery learning (that would produce understanding, though with less computational skill, except that it’s being implemented by math-phobic ditzes) happens to be when they go through their program.
My mother, my daughter and I all attended the best private high school in Atlanta, hands down - we scrimped and saved to pay for it, it is not significantly more expensive than any other private school here (they are all within about a couple hundred of each other, except some of the new startups).
When I was there in the 70s, and when my daughter was there in the 00s, there was not ONE teacher on the premises with an "Edumakashun" degree. Teachers held advanced degrees, usually in their area of study. Lots of doctorates. My German teacher was an exception with a doctorate in chemistry from the University of Graz in Austria (her husband taught chemistry at Ga. Tech). Her German V class used to go to the state contest in Athens and run the table. Nothing like being taught by a native!
School pays teachers less than the public system - but people are knocking down the doors to work there because the kids are very bright, want to learn, and excel.
On the other hand - when I was between jobs with young children at home, I thought it would be a nice thing to substitute teach in the City of Atlanta system. Mind you, I have an honors degree in history from an Ivy and a law degree from a good regional school. I am also certificated to teach dance and horseback riding, so I know how to teach a class. But I do not have an "Education" degree - so the city system wasn't interested. These are people who have sub-literate fourth grade teachers (I took the deposition of one of them once. She could not read beyond maybe a 5th grade level.)