Teachers unions like the NEA and AFT aren't supposed to be focused on education. They're supposed to look out for the best interests of teachers--in other words, they're supposed to focus on the pay, benefits, and working conditions of teachers. They're not supposed to worry about education or students at all--legislatures, parents, and school boards are supposed to worry about those topics.
This article seems to express concern that teachers unions focus on teacher jobs:
But two-thirds of U.S. voters (66%) say the teachers’ unions – the National Education Association and the American Federation of Teachers – are more interested in protecting their members’ jobs than in the quality of education.
Only 23% of voters say educational quality comes first for the unions, according to a new Rasmussen Reports national telephone survey. Twelve percent (12%) are undecided.
I'm more concerned that the NEA is a far-left-wing political organization and not really a teachers union. I'm not concerned at all that it isn't focused so much on education.