Deborah Appleman, the chairwoman of education studies at Carleton College, shadowed a former student of hers through the summer training of TFA's first class in 1990. She came away disappointed and has been been a persistent critic ever since. She discourages her students from applying and refuses to write letters of recommendation for them.You might also want to take a look at Barnett Berry's blog post at District Administrator in which he does the math:
Critics like Appleman . . . say that TFA's premise—that corps members can succeed without substantial training in the classroom—is "insulting" to professionally trained teachers. Without such training, she's convinced, TFA teachers often disserve their students, and themselves, because their struggles discourage them from staying in teaching. Too high a share (30 percent that first year, 12 percent on average overall) leave before completing their two-year commitment, Appleman argues.
Lincoln Caplan, who penned the Slate exposé of TFA, reports that over 15 years the non-profit has spent $500 million (30 percent from the government) to recruit a few thousand teachers who will remain in the classroom no more than two years. (Caplan’s investigation reveals that over a decade and a half about 8,000 TFA recruits remain in education, with no more than one-half actually teaching children.) It has been difficult to get the accurate numbers on TFA, but it looks like Caplan's research would signify that TFA is spending about $125,000 per teacher!