Did anyone ever think of the real source of the problem? There are two sources that we can be sure of, and there may be more. Where do teachers get their training and degrees? One has to look at the colleges and universities that are producing professionals who teach the children in this country.
The blame seems to always be placed on everybody but the "teacher mills" that provide the training and degrees to get certification. If colleges and universities are fulfilling their duty, then there is one more source, the parent or guardian.
Teachers' unions and associations serve to acquire fair treatment for their members who have been trained by colleges and universities and certified by states or local boards of education. Private schools, public schools, charter schools and home schools all use or should use the products of the colleges and universities. There needs to be fairness in the blame game.