The June 2006 edition of Readers Digest has a good article on Wendy Kopp the creator of Teach For America, the national teacher corps. It's like the Peace Corps except instead of going overseas, participants teach in inner-city and rural schools. I'm also an alumnus.
The organization has grown considerably since I was in the Mississippi Delta corps from 1992-1994. TFA is certainly more organized and efficient, but I wonder if it retains the entrepeneural spirit that existed. Back then, ideas about teaching and leadership were coming fast and furious. The organization was very experimental. We would discover (or more likely rediscover) good ideas and reject plenty of bad ones. At least we learned from our mistakes. Most emerged from teaching a bit less naive, more experienced, and committed to Teach for America's mantra--"Every child deserves a quality education."