A new report by Julian Vasquez Heilig and Su Jin Jez reviews the evidence about the effectiveness of Teach for America.

Their study, published by the National Education Policy Center, “challenges the simplistic but widespread belief that TFA is a clear-cut success story. In fact, Heilig and Jez find that the best evidence shows TFA participants as a group are not meaningfully or consistently improving educational outcomes for the children they have taught.”

They find that:

Teach For America and other organizations have produced studies asserting benefits provided by TFA teachers. Those studies, however, have only rarely undergone peer review – the standard benchmark for quality research, Heilig and Jez observe. In contrast, the available peer reviewed research has produced a decidedly mixed picture. For example, the results attributed to TFA teachers varies both by their experience and certification level. The results also fluctuate depending on the types of teachers to whom the TFA teachers are compared; TFA teachers look relatively good when compared to other inexperienced, poorly trained teachers, but the results are more problematic when they are compared to fully prepared and experienced teachers, Heilig and Jez report.

Because of these differences, the question most frequently asked—Are TFA teachers “as good as” teachers who enter the profession through other routes?—is not the question we should be asking, Heilig and Jez contend. Whether one or the other group is better is “a question that cannot be answered unless we first identify which TFA and non-TFA teachers we’re asking about,” they write.

Even more important, “The lack of a statistically and practically significant impact should indicate to policymakers that TFA is likely not providing a meaningful reduction in disparities in educational outcomes, notwithstanding its explosive growth and popularity in the media,” according to Heilig and Jez. Moreover, despite its rapid growth, TFA remains a tiny fraction of the nation’s teaching corps; for every TFA teacher, there are 50,000 other teachers in the U.S., Heilig and Jez note, and the small numbers and small impact of TFA point to a needed “shift in thinking.”

“We should be trying to dramatically improve the quality of teaching,” write Heilig and Jez. “It is time to shift our focus from a program of mixed impact that, even if the benefits actually matched the rhetoric, would not move the needle on America’s educational quality due to the fact that only 0.002% of all teachers in the United States are Teach For America placements.”

In other words, those who seek long-term, systematic improvement of the teacher force in the United States will not find an answer in Teach for America. Their numbers are few, and not many remain in teaching.

Those who want real change must concentrate on improving the working conditions of teachers so that it is an attractive option for college graduates, and must focus on raising standards for entry into the profession as well as strengthening the quality of professional preparation and support for new teachers.