The Flying Classroom, (in the original German Das Fliegende Klassenzimmer), is a 1933 novel for children written by the German writer Erich Kästner.
The story covers a few days left for the students of Johann-Sigismund Gymnasium before Christmas. The main characters - students from Quarta (Year 7) - are rehearsing a Christmas drama called 'The Flying Classroom' when their attention is distracted by a brawl against the students of the local Realschule. The depiction of the "war", taken very seriously by both sides, seems to be Kästner's wry way of commenting on grown-up wars, nationalism and patriotism. The protagonists then find out that the Nichtraucher, or non-smoker, the man who lives in a surplus second class non-smoking car lying in the Schrebergarten, is actually the long-lost best friend of their much-beloved teacher, Der Justus. They then try to reunite the long-separated friends, while coping with their own individual problems.
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das Fliegende Klassenzimmer Trailer