The Demerits of Merit Pay

The powerful National Education Association has held a firm line against salary systems based on teacher performance, preferring the traditional system that ties pay to experience and advanced study. They say those factors are most closely linked to good teaching.

But the American Federation of Teachers has been more supportive of local experiments, as long as teachers are included in their design.

"We take a very careful look at the level of collaboration that teachers have in creating these plans," said Jackson. He added that professional supports — mentoring and teacher development — are as important as the money that goes with it.

Florida legislators were shocked last year when few teachers agreed to compete for incentive pay, tied to student test performance. The plan's prospects have improved, since lawmakers redesigned the program to lessen the importance of test scores, and to allow teams of teachers, rather than just individual teachers, to quality.

A growing number of local unions have agreed to experiment with alternative pay structures, especially to encourage teachers to move to low-performing schools or to teach high-needs subjects, like math and science.

Promising programs are underway in Denver, Chicago, Austin, and Minneapolis, among others. Many distribute bonuses throughout the school — even janitors and lunch ladies can qualify.

And the pot of money is growing.

Since last November, the U.S. Department of Education has awarded 33 grants to pay out more than $477 million over the next five years. That money will go toward teacher incentives that improve student achievement, and close achievement gaps in high-poverty schools. Many millions more in private funds have also been distributed.