I was a public school teacher in the Boston area (this was years ago).
I have never had any problem sending my kids to public schools. I believe that most teachers do exactly that.
Public schools in the United States are in general quite good. There are problem areas, but the problems are related to location. We segregate in this country by race and social class... and schools in poor areas have problems.
Teachers are educated. They generally live in suburbs with good schools.