One reason may be that the TFA experience often doesn't feel that empowering. And the research on civic participation (to simplify a lot) indicates that if you have a disempowering civic experience that will, not surprisingly, turn you off to civic engagement as a tool for social change.
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“There’s been a very clear and somewhat naïve consensus among educators, policy folks and scholars that youth activism invariably has these kinds of effects,” Professor McAdam said. “But we’ve got to be much more attentive to differences across these experiences, and not simply assume that if you give a kid some youth service experience it will change them.”
Last year, 35,000 people applied to Teach for America, 42 percent more than in 2008. Further, at more than 20 colleges and universities, Teach for America was the top recruiter. At Harvard, 13 percent of graduating seniors applied. At Spelman College, in Atlanta, 25 percent did.