Chicago Teachers Union members are picketing outside the Chicago Board of Education headquarters and schools throughout the city this morning in the first day of a strike. CTU officials are also expected back at the bargaining table today to negotiate unresolved issues for a new teacher contract.

As PI reported last night, what those issues are remains a matter of dispute. Chicago Mayor Rahm Emanuel says all that's left is an agreement regarding teacher evaluation procedures and a principal's power to make personnel decisions. But CTU President Karen Lewis says that a host of issues are unresolved, including teacher health benefits and work environment issues, like classroom air-conditioning.

Check back with PI later today for more on the CTU strike.