Boarding School of Girls(1981)

Original title: Internatsgeheimnisse junger Mädchen

Christine has some misadventures on her way to boarding school (more like a reform school). After speaking to her father on the phone while he is being given head by Ulrike Lary, she witnesses a shop being robbed while the owner is having sex with a female. She is raped by the taxi driver who picks her up at the station and then molested by the policeman to whom she reports this incident.