Performance pay, of a sort, is coming to several school districts in Michigan. The Mackinac Center for Public Policy gives the details in its publication Michigan Education Report.

In the abstract, this is a good: schools are responding to market pressures, and teachers get paid for performance.

As practice, however, the plans are fairly modest. Most apply a bonus of less than 1 percent of teacher salaries. They're also not always linked to improvements in student performance. In Grand Rapids (the state's second-largest city), school employees could get a 1.75 percent bonus if the school district loses fewer than 100 students.

It's not clear that the logic of merit pay is actually being embraced by the Michigan Education Association, arguably the state's most important union. Said one local union official: "We didn’t look at it so much as an incentive, (but) as a bonus for the hard work they had put in." Another said: "I wouldn’t call them incentives. They’re more indicators."

So will these plans be baby steps towards a competitive market for education and merit-pay plans, or vaccines against the real thing?