This year North Carolina's Guilford County launched an incentive plan to attract and retain qualified teachers for the district's low-income schools. The plan is aimed primarily at much-needed math teachers. Most math teachers in low-income schools can now earn an extra $9,000 annually; Algebra II teachers earn an extra $10,000. On top of that, these teachers can earn up to $4,000 more depending on student progress.

These golden carrots dwarf similar pay incentives found in other districts, and the effort seems to be paying off. Guilford's Superintendent reported that all of the positions offering extra pay were filled this year, though the district still faces the challenge of vacancies in other hard-to-staff subjects like science that are not yet tied to incentives.

The North Carolina Association of Educators teachers' union is skeptical, particularly because a number of teachers with questionable performance were transferred out of their schools once the plan was in place. "It's not fair, and it begins to pit teacher against teacher," said NCAE Executive Director Kevin Spragley. "All teachers should be paid more, and it will entice more people to the profession in all subjects."

Superintendent Terry Grier, however, remains optimistic--and makes the right point. "I think it will make a difference," he said. We've been differentiating salaries for years. It's just been by experience and degree."