April 19, 2010 4:32 pm North Penn Teachers Walk Picket Lines North Penn teachers were out of the classroom Monday and no school was expected Tuesday as the union and the district battle over contract demands. US & World Videos 9:46 Another NJ earthquake: The Lineup 2:54 Penn leaders reiterate to pro-Palestinian protesters that they need to pack up camp 1:44 Pro-Palestinian protesters remain on UPenn's campus despite warnings to disband 1:30 Protests calling for ceasefire continue at Penn 6:33 Family affair: Former Eagle and new Eagle Jeremiah Trotter and Jeremiah Trotter Jr. speak out