The thing we need to realize is hat schools are too large. If there is a large school district you need a union to represent the teachers. If there were hundreds (perhaps thousands) of school districts in Chicago, then each school could be run by parental participation, not get lost in the Bureaucracy. If the many small districts competed for teachers with wages and benefits, then there would be no need for a union as each person becomes a contractor to a small unit.
It is time to bust the large school districts up. Let each school vote and let each parents control ones own child's education. If people can vote with their feet individuals get the best, or worst depending on each person's own preferences.