"It is frustrating. It's disheartening and discouraging to think that someone would want to work that hard to close schools," said Brandon Cooley, principal.
Last week, someone set fire to the Penn Wood High School's Lansdowne branch. It forced the district to move the 11th and 12th graders to the Cypress Street branch in Yeadon.
With all 1500 students doubled up in one building, the last thing they need is another disruption.
The school was emptied Friday morning when someone called 9-1-1 threatening to blow up the school.
Police searched and didn't find any explosives but, the damage was done, and another school day was lost.
The students are just as frustrated as the staff.
"If we don't finish these days out, we're going to have to add them on at the end of the year and that's going to mess our summer up a little bit," said Niaire Brown.
The district had another bomb threat the week before the arson fire at the high school in Lansdowne.
Pam Thornton's two daughters are recent graduates. She says bomb threats have become commonplace.
"These bomb threats have been going on for years. I'm surprised that something has happened now as opposed to years ago," said Thornton.
Friday's disruption came during a show of unity in the face of the recent adversity.
Staffers wore these red shirts declaring "Penn Wood Strong-United."
"It's just going to galvanize us even more as a community and student body but at some point it's got to end," said Cooley.
Meanwhile the police are hoping it ends with the arrest of whoever's responsible for the fire and bomb threats.
Congressman Bob Brady is now calling on the U.S. Attorney to launch a federal investigation into the incidents.