Currently, it is nearly impossible for schools to fire incompetent or under-performing teachers. In addition, it is difficult to incentivize teachers because the best ones can not be compensated more than the worst ones.
Teachers unions are currently concerned with protecting their due-paying members, not with educating our country's children. Money from the teachers unions is put into the pockets of our politicians pockets, hindering reform. Clearly, the incentive of money overcomes the desire to educate our youth. Therefore, allow this powerful lever that has done much damage to be applied productively where it is needed: teachers salaries.