Always Trouble with the Teachers (1968)

Peter Hartung, a student at the technical college, just wanted to take his little brother Paul to boarding school. On the way there, his friend Hans Werner tries to persuade him to swap roles. Peter wouldn't dream of going to school for Hans, but only changes his mind when he makes the acquaintance of Christa, who works at the neighboring fashion school. He has no idea that Christa has just broken off her engagement to Dr. Werner, his future literature teacher. The lessons with his jealous ex-fiancé turn into a gauntlet, but this does nothing to dampen the general good mood. Brother Paul also causes a lot of excitement. Not a day goes by without him plotting a prank. Within the sacred school walls, the wildest boarding school comedy since the introduction of compulsory education unfolds - explosions, police action and fire alarms - but principal Dr. Schwabmann takes it all in his stride.