David Kraegel pleaded no contest in Lancaster County Court on Monday to third-degree sexual assault in the case.
Police say the 63-year-old Kraegel was dropping off the girl in June when a couple in the area saw Kraegel and the girl embracing. The couple told officers they boarded the bus and asked the girl if she was okay. Kraegel said he had been helping the girl crack her back.
The neighbors called police, and offices say the girl told officials Kraegel had kissed and touched her.
Kraegel's sentencing is scheduled for Oct. 2.