Goofs

The way the word "Autokratie" is written on the black board changes between shots.

(at around 15 mins) The teacher is formally called Rainer Wenger, although informally he uses his first name is Rainer, among his students initially and later his surname during the project, Wenger. One might think the principal would use his first name when talking to him, but in Germany when adult colleagues speak to each other, they use their last name when talking to each other, i.e. Herr Wenger.

The word "Montag" (Monday) is not reflected properly on the lake's surface, esp. as opposed to "Dienstag" (Tuesday), which has its proper reflection on the school's floor.

The action is clearly set in the 21st century, but the license plates of most or all cars begin with 'BE' (district 'Beckum', North Rhine-Westphalia). These licenses expired on January 1st, 1975. (This surely is intended to set the action 'somewhere in Germany')

Although set somewhere in western Germany, all policemen wear insignia of the state of Berlin.