Chicago public school teachers walk a picket line outside Lane Tech High School on Tuesday, Sept. 11, 2012, on the second day of a strike in the nation's third-largest school district. Negotiations by... more 
Chicago public school teachers walk a picket line outside Lane Tech High School on Tuesday, Sept. 11, 2012, on the second day of a strike in the nation's third-largest school district. Negotiations by the two sides failed to come to an agreement Monday in a bitter contract dispute over evaluations and job security. (AP Photo/Robert Ray) less 
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Associated Press | Photo By Robert Ray
Tue, Sep 11, 2012 6:39 PM EDT