"The Bad New Bears robbed us," Rap Curry, the school athletic director, said Wednesday. "They didn't take the extra-large stuff."
Curry calls the loss "a bigger hit than just football equipment" in a district with limited resources. The school does not have the budget to buy new equipment each year, he said.
The school and teams take exceptional pride in caring for what they have. Curry estimated the loss at $10,000, but inventory-taking continues. The equipment was temporarily housed at the facility after a fire at the high school in April.
"A game football costs $70," he said.
He said the worst loss was the generator, which powered the ball-throwing machine and the hitting machine for the girls' softball team.
"For us to have a football-toss machine is a big deal," Curry said.
"We are always counting our pennies and nickels," he said. "We are going to have to make it up somewhere, whether it is a few less trips or a fund-raising plan. We'll figure it out."
On Wednesday, Curry, an alumnus of the school and a former St. Joseph's University basketball player, was scrambling to find replacement equipment for the game. The Patriots' first game is 11 a.m. Friday, when they play West Chester East at their home field.
Some players may not have logos on their helmets, and the trainers may have to use a folding table, but the game will go on, he vowed.
"One day we'll figure out who it is," Curry said. "You can't be a leader and steal."
The thefts are yet another setback for the school.
In April, a three-alarm fire heavily damaged the school, in Lansdowne, closing it for the rest of the academic year. The school housed the district's 700 juniors and seniors, who were relocated to the Cypress Street campus in Yeadon, the facility for freshmen and sophomores.
The blaze followed a series of bomb threats.
No arrests have been made in either case. A $22,000 reward is offered for information that leads to an arrest.
Yeadon Police Chief Donald Molineux does not think the break-in was related to the two other incidents.
"It is a shame, all these communities, including the William Penn School District, are struggling budgetary-wise," Molineux said.
With a general lack of property wealth, the towns in the district have some of the highest effective tax rates - the annual tax bill as a percentage of market value - in the region and nation.
"This is just another thing that will impact on the school budget for the year," he said.
Donations can be sent to the William Penn High School Athletic Department, 100 Green Ave., Lansdowne, Pa. 19050.
Contact Mari A. Schaefer at 610-313-8111, firstname.lastname@example.org, or follow at @MariSchaefer on Twitter.