Bathing scene with Antoine. When the phone rings he gets out of the bath. When mother comes in, he quickly jumps back into the bath. Brief rear nudity in the mirror. When mom leaves, he gets up out of the bath. Very brief frontal nudity. He examines himself in the mirror, where he sees himself with huge muscles and a speedo.

The boys (aged 15-19) are seen from the rear measuring their penises.

Boy's nude bottom seen after punishment.

The season 5, 12th episode "Stefans Geheimnis": When Stefan (Christian Blümel, 14) realizes that he's gay he tries to cut his penis with a razor blade, standing nude in the bathroom (side/rear).

Imanol (14) gets undressed and stands naked in front of the mirror. The mother comes in and catches him posing. Rear nudity.

Soon thereafter he nicks a book on human anatomy, and that evening while in the bathroom, measures the size his own genitals to the pictures in the book.