The Flying Classroom (German: Das Fliegende Klassenzimmer) is a 1933 novel for children written by the German writer Erich Kästner.
In the book Kästner took up the predominantly British genre of the school story, taking place in a boarding school, and transferred it to an unmistakably German background.
The story covers the last few days of term before Christmas for the students of the Johann-Sigismund Gymnasium. The main characters are Martin, the first student of the class, Jonathan, an orphan who was adopted by a captain, Matz, Uli and Sebastian, students from the Tertia (Year 8). There is a bitter struggle between the students at the Gymnasium and another school, the Realschule. The so-called "Realists" steal their schoolbooks containing their dictations, which the teacher's son (another classmate) was to carry home to his father. The son was also captured by the 'Realschüler'. This results in a brawl between two champions of each side - Matz and one Wawerka - and a hard-fought snow-ball fight, both of which the six friends win, although they end up being reported by a student from the Prima (Year 13) for being late back to school. As a "punishment" they are docked one afternoon's leave, which they are invited to spend with their amiable house teacher Dr Johann ("Justus") Bökh at his office (coffee and cake included) where he tells them a story about his own youth and his struggle with unreasonable prefects from the Prima.
Other parts of the plot include: the friends playing a drama called the Flying Classroom written by Johnny, their friendship with the "Nonsmoker" (a former doctor who lives in an scrapped non-smoker railway compartment and works as a pub piano player) and the Nonsmoker's own friendship with Dr Bökh, with whom the boys help to re-unite him. Uli, the smallest boy, decides at this time to attempt something which will remove his reputation as a coward. His best friend, Matz, has in the past encouraged him to try to shed it, but he is horrified when he sees Uli about to jump off a tall climbing frame using an umbrella as a parachute. Uli crashes to the ground and falls unconscious. As the boys know that the Nonsmoker used to be a doctor, they fetch him, and he allays their fears that Uli is dead. However, he has a broken leg (in the Canadian version, Uli breaks an arm instead). Upon this, the Nonsmoker re-enters the medical profession as he becomes the new school doctor.