There have been plenty of films set in the classroom over the years, from Goodbye, Mr Chips to The Dead Poets Society, not to mention female-led films such as Mona Lisa Smile or Dangerous Minds. In all the above, the teacher is the hero of the piece. In German director Ilker Çatak’s The Teachers’ Lounge, however, the teacher is far from being a hero, despite her good and honourable intentions.

The film opens with the camera following maths teacher Carla Nowak (Leonie Benesch) as she strides purposefully into school and makes her way to the teachers’ lounge before heading to class. Before the film has even got going or a line has been spoken, Çatak alerts his audience to the fact that this film is no School of Rock. Thanks to Marvin Miller’s truly disturbing score, the tone is set for a psychological thriller that will set the nerves on edge. Cinematographer Judith Kaufmann builds on this tension visually with her palette and the ominous shadows of the teachers’ lounge.

Carla is young, fresh faced and eager to make a difference. She starts her lesson with a happy-clappy greeting that seems a little out of place considering the age and sophistication of her pubescent pupils. (She pulls a similar stunt at a later point in the gym, where a trite trust-building exercise soon spirals out of her control.) Nevertheless, she seems well liked and the class appears to be harmonious and up for a bit of clapping if it makes her happy.

But there is an insidious problem threatening the class’s equilibrium: thefts have been taking place and one of her students is almost definitely the culprit. The teachers call in the two class representatives and there is an interrogation of sorts as the grown-ups try to coerce the children to offer up a name. When the name is dragged out of the kids, it transpires the potential perp is of Muslim Turkish origin. When the mother raises the notion of the school’s racism being behind the accusations, Carla sides with her student and his parents. However, when she becomes embroiled in catching a thief in the teachers’ lounge, she creates problems that have far-reaching repercussions for herself, her students and her co-workers as a consequence of her well-intentioned but misfiring actions.

Throughout the film, Çatak provides examples of how the school hierarchy operates. It appears students have some say in how the school is run – they have class representatives, they are party to talks and can vote on proposals – but that democracy and participation counts for nothing when the big decisions are made. It is only when the students rebel that they hold any real power. Çatak, who cowrote the screenplay with Johannes Dunker, creates a teachers’ lounge that should be a haven for the severely overworked staff but which is in fact a bit of a vipers’ den that mirrors your average classroom with the same bullies and thieves, and bitches and buddies. Instead of being a place of solidarity, Carla quickly finds herself virtually friendless and ostracised.

Benesch is the glue that holds this film together, appearing in every scene. She starts out as a confident idealistic teacher and ends up having panic attacks in the toilets, breathing into a used plastic bin liner. She is bruised, literally and figuratively, by the events that have unfolded, and she is completely believable. When once she started her lesson with a cute chant, in her final lesson we see her start with a primal scream.

Despite the drama, the situation does not spiral out of control – this is no We Need to Talk About Kevin – but some of the beautifully crafted tension introduced in the early part of the film is lost towards the end, the final scene particularly disappointing. But this is a smart film about the microcosm of the world that is school, with all its human fallibilities and injustices. If you’re thinking of taking up the teaching profession, this film might make you consider a new career path.