Die Feuerzangenbowle

During a Stag Night where his friends exchange anecdotes about their old school days, the well-known writer Dr. Johannes Pfeiffer cannot join in. He was taught by a private tutor. In order to recover his lost youth, Dr. Johannes Pfeiffer changes into Hans Pfeiffer, a schoolboy in a small town high school. With ever more foolhardy pranks, he drives the assembled teaching staff completely mad - discovering along the way the woman of his life: Eva, the daughter of the schoolmaster. (filmportal.de)