Chicago school teachers picket outside Wells High School on September 10, 2012 in Chicago, Illinois. More than 26,000 teachers and support staff hit the picket lines this morning after the Chicago Teachers Union failed to reach an agreement with the city on compensation, benefits and job security. With about 350,000 students, the Chicago school district is the third largest in the United States. (Photo by Scott Olson/Getty Images)
Chicago school teachers picket outside Wells High School on September 10, 2012 in Chicago, Illinois. More than 26,000 teachers and support staff hit the picket lines this morning after the Chicago Teachers Union failed to reach an agreement with the city on compensation, benefits and job security. With about 350,000 students, the Chicago school district is the third largest in the United States. (Photo by Scott Olson/Getty Images)
