I find Shanker Blog’s Matt Di Carlo to be a reliable and very fair minded source for education research coverage despite coming from a somewhat different part of the ideological spectrum than I do on education reform. He has an assessment of the literature on TFA that I recommend.  Although I don’t know this area of research very well, his discussion reflects my general impression. Here is how he summarizes:

 One can quibble endlessly over the methodological details (and I’m all for that), and this area is still underdeveloped, but a fair summary of these papers is that TFA teachers are no more or less effective than comparable peers in terms of reading tests, and sometimes but not always more effective in math (the differences, whether positive or negative, tend to be small and/or only surface after 2-3 years). Overall, the evidence thus far suggests that TFA teachers perform comparably, at least in terms of test-based outcomes.

I also Matt is correct to look to the meta lessons about TFA and teachers in general, but I disagree somewhat about the meta lesson. He says:

But, to me, one of the big, underdiscussed lessons of TFA is less about the program itself than what the test-based empirical research on its corps members suggests about the larger issue of teacher recruitment. Namely, it indicates that “talent” as typically gauged in the private sector may not make much of a difference in the classroom, at least not by itself.

In contrast, I would say the lesson from TFA is that “talent” as typically gauged in the private sector makes as much of a difference as an entire four year teaching education does. If talent didn’t matter much, then you could give all teachers five weeks of training instead of four year educations and the outcomes would be comparable to what we are seeing now. Either talent doesn’t matter much or going to college for four years doesn’t matter much, in either case one is about equal to the other on average.

One thing this lesson implies to me about policy is we should think about how we can combine the most important aspects of the four teacher year education and boil it down to something more than five weeks and less than four years in order to make it easier to recruit people with TFA level talent into teaching. We should be experimenting more with alternative credentialing regimes for teachers.

ADDENDUM:  In response to BSEconomist’s comment let me clarify. The evidence shows a lot of ability is worth about as much as a full teaching education. Yet we only allow two choices: a lot of ability with very little education (TFA), or a full education. We should allow a wider variety of substitution of ability for training  instead of just all or almost none.