Teacher bonuses not linked to better student performance, study finds

"While this is a good study, it only looked at the narrow question of whether more pay motivates teachers to try harder," said Peter Cunningham, assistant U.S. education secretary for communications and outreach. "What we are trying to do is change the culture of teaching by giving all educators the feedback they need to get better while rewarding and incentivizing the best to teach in high-need schools, hard to staff subjects. This study doesn't address that objective."

Administration officials say a federal program that backs performance pay in dozens of school systems has grown to $400 million a year, from about $100 million when Obama took office in 2009. Federal officials say a number of such efforts have shown promising initial results; they also are planning a comprehensive review of the program.

Eric A. Hanushek, an expert on the economics of education at Stanford University's conservative-leaning Hoover Institution, said the Vanderbilt study did not address a key question.

"The biggest role of incentives has to do with selection of who enters and who stays in teaching - i.e., how incentives change the teaching corps through entrance and exits," Hanushek said. "I have always thought that the effort effects were small relative to the potential for getting different teachers. Their study has nothing to say about this more important issue."

Erick Huth, president of the Metropolitan Nashville Education Association, a teachers union, said the study raised significant questions about "the extent to which we spend a lot of time trying to develop complex schemes to measure teacher performance and then reward [teachers] based on that performance." He said the study indicates that such efforts "may be a waste of time."

In the D.C. school system, teachers deemed "highly effective" based on test scores and other measures began receiving bonuses this year of up to $10,000, as well as other potential compensation benefits. The performance pay plan, a cornerstone of Rhee's effort to overhaul the city schools, is backed by a new contract with the Washington Teachers' Union and funding from private foundations.

Prince George's is entering the third year of a performance pay program that offers some teachers up to $10,000 based on good evaluations, improved student test scores and other factors. Superintendent William R. Hite Jr. said that there is some evidence that teacher retention has improved but that it is too early to say anything about student academic performance.

Staff writers Bill Turque and Michael Birnbaum contributed to this report.