Straßenserenade

Pepe Nietnagel's father has a valuable stamp collection stolen in Amsterdam. Street musician Pit recovers it. To show his gratitude, Pit is invited to Baden Baden and enters the Mommsen Gymnasium. There, he joins Pepe in his pranks.

Pepe Notnagel (who inexplicably had his name changed from the first movie's Nietnagel) and his classmates scheme to get around doing any actual school work by cheating or sending their teachers to the sanatorium. A Swiss documentary film maker disguises himself as his brother in law, who got a position as an exchange teacher, to aid his project of making a movie about the current youth.

Leopold, head waiter at the "Weißen Rössl" (White Horse Inn), is secretly in love with the beautiful waitress Josepha. But she's only interested in the lawyer Dr. Siedler. Jealous, Leopold comes up with a plan to gain Josepha's attention.