Chicago teachers were anxious this morning as they walked the picket line for the seventh day, worried whether union officials will decide today to call off the strike that has kept 350,000 students out of the classroom. "I'm hoping the delegates come to their senses and know that our kids need us," Mary Silva, a CPS social worker, said outside school headquarters. The Chicago Teachers Union's House of Delegates is to meet at 3 p.m. to go over a tentative contract reached during marathon negotiations last week. It could decide to end the strike while a ratification vote is taken...