Keith Steininger, 68, of Upland Borough is being held in lieu of a $250,000 bond, prosecutors said.
Investigators say Steininger, who was also a Boy Scout trooper leader, abused the victim for a period of two years between 2018 and 2020, when the victim was between 11 and 13.
Authorities said Steininger was the victim's Boy Scout leader and former teacher at Girard College, a Philadelphia boarding school for children from families headed by a single parent or a guardian. The alleged assaults took place while the victim was staying with Steininger, the DA's Office said.
The investigation began in January after the victim told a foster parent who notified Upland police, according to prosecutors.
"The defendant in this case worked with children, many of whom were particularly vulnerable by virtue of coming to Girard through the foster care system, for more than 41 years," said DA Jack Stollsteimer.
"He was placed in a position of particular respect by becoming a Boy Scout troop leader. It is both heartbreaking and deeply disturbing that such an individual would take advantage of a vulnerable child."
Steininger's preliminary hearing is scheduled for May 2.
Click here to follow Daily Voice Drexel Hill-Upper Darby and receive free news updates.