The girls appearing naked in the locker room scene weren't professional actresses but real 16-year-old students at Kvarnbackaskolan in Kista, Stockolm.
In one scene- in Kvarnbackaskolan's gymnasium - Leif Andrée is bullied by his pupils. Stig Larsson had given strict instructions. With the cigarette in his mouth and a beer in his hand, he made it clear that the gym teacher was a legitimate object of hatred. The children had to hit as hard as they wanted. "We managed it on the first shot. They hit me and threw the ball in my head. It was really violent. I had a sore ass for several weeks afterwards. "-Andrée says.