Occupation: Founder and CEO, StudentsFirst
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Michelle Rhee gained national notoriety as the controversial chancellor of District of Columbia public schools when she launched an overhaul of the troubled system, closing dozens of under-capacity schools and proposing an end to teacher tenure in exchange for higher, achievement-based pay. She was portrayed as an education superhero of sorts in Davis Guggenheim's Waiting for "Superman". But it was her resignation as chancellor and subsequent launch of StudentsFirst, an advocacy organization aimed at overhauling public education, that cemented Rhee's place as a woman on a mission. In announcing the formation of StudentsFirst on the Oprah Winfrey Show, Rhee said, "I am going to start a revolution. I am going to start a movement in this country on behalf of the nation's children."