Not all public schools are bad. I live in a rural area in the midwest and I have to say my boys elementary school is excellent. They are two years ahead of where I was at their age. It is a conservative area of the country and the school board reflects the demographic. We moved here from Ga. just to get away from some of the horror stories we had been hearing about the public schools there.
I contend that they are due to the watered-down curricula. (I believe you when you say that there exist “good schools”, with good people, etc., but what do you get when good people are pushing a bad product/bad curriculum? Answer: Our dumbed-down schools.)