Em Dash Parr’s review published on Letterboxd :
A teacher conducts a social experiment to show his students the life under dictatorship/autocracy. He orders his students to call himself Mr. Wenger (instead of the usual Rainer, his first name). The students are also required to be more discipline and speak brief, articulate sentences. At first it goes very well, because the lesson feels real and the students are more interested. Heck, I would love to be in that class. The bullies befriend the bullied because they are now equal (they all wear white (ironically?)). But then the students take the experiment to another level, by naming their little community the titular The Wave or Die Welle and invent a salutation gesture. They make their own symbol and paint graffiti all over the town. Chaos ensues.
I think The Wave shows how influential a teacher can be and how easy it is to manipulate the masses, though in this movie it all seems exaggerated because... I don't know, it all happens only in a week and it feels like a really short time for the students to be that... united.
The movie starts out strong but by the end of it, it feels a little too unbelievable. Nevertheless, The Wave is a very fun drama-thriller and I would recommend it!