What do you think of merit-based pay for teachers?

Merit pay, or compensating teachers for classroom performance rather than their years on the job and coursework completed, found some support in the 1980s among policy makers and school administrators, who saw it as a way to encourage good teachers to work harder and to weed out the bad ones. But teachers saw it as a gimmick used by principals to reward cronies based on favoritism.

Commentary: http://news.blogs.nytimes.com/2007/06/17/merit-based-pay-for-teachers/