Merit-based pay rewards the best instructors and punishes the worst instructors.
Like all jobs, merit pay motivates in a way that results in more effort and better performance.
It weeds out the cynical, burned out teachers that have coasted on tenure for far too long.
Teachers will be motivated to try new approaches if an old one isn't working.
In an effort to get the best results, teachers will seek out modern teaching technologies involving
computer-based training, Internet podcasts, Ipad apps, etc.
How can teachers honestly convey to students that performance is important when they themselves
don't want to be judged on performance?
Merit-pay brings out a spirit of competition with peers, which gives teachers yet another motivator
to do well.
What's best for students should be the focus of educational efforts; not the teachers.
Teachers from the inner city and/or poorer neighborhoods have far more obstacles to overcome and
can't be judged by the same scale as teachers from more advantaged areas.
Teachers start emphasizing student performance on the tests that determine their pay rather than the overall
knowledge, ability, and development of the student.
It could lead to more tolerance of cheating, as failing such students would lower their own performance-based
pay. In addition, teachers themselves could cheat on test-scoring.
It will provide another disincentive for people to teach in disadvantaged areas. Pay must usually be higher
to draw education graduates to such challenging and potentially dangerous teaching districts.
Most teachers don't enter their profession for money, so performance-based pay may not have any effect.
Given the massive political power of teachers' unions, such a performance-based system will never pass, so it's
a waste of time to even consider it.
The best teaching attributes--inspiration, motivation, etc.--are nearly impossible to measure.