I went to public school and had some great teachers who were worth their weight in gold. I also had other teachers who weren't worth a nickel and did a great amount of harm to their students.
If teachers' unions ever agree to let teachers be paid based on how good they are - rather than just by seniority - you might actually see more attractive salaries for good teachers.
The problem is how do you determine how "good" a teacher is? If it's based on student performance then what about the teacher that gets stuck with a class full of idiots? Maybe they're a great teacher doing the best they can but they can't get anywhere because the principal took all of the smart kids and moved them to the classroom of the teacher blowing him on the side so she gets bonuses. The only way to objectively measure a teacher's performance is by auditing their work and that's way too expensive to ever happen. So the crisis continues.