In 1989, Wendy Kopp founded Teach for America.  This organzation recruits new college graduates to teach in low-income schools.  Since that time, 14,000 teachers have gone through this program.  The story in the New York Times talks about how the Teach for America almuni have moved forward and begun their own charter schools.  Read about it here. This is a great example of how one person can change the lives of so many through their dedication to teaching.