Chicago teachers began walking the picket line for the first time in 25 years Monday morning, leaving parents to scramble for alternatives for their children. .....Steve Parsons, the lead picket who teaches AP psychology at the high school said Monday: “It’s all up to Mayor Emanuel. We all want to go back to the classrooms. The mayor is not valuing our opinions as educators.” .....Vitale said the contract amounted to a 16 percent raise over four years for the average teacher when factoring other increases. And the raises could not be rescinded for lack of funds — which is what...