The movie was filmed between October 1979 and June 1981. The scenes were shot in the same chronological order in which they appear in the film.
When Nils Malmros called Gitte Iben Andersen and told her that she had become the chosen one to play Lene, she noticed that there was also a nudity scene. She was therefore refusing - but nevertheless said yes, when the film director added in a slight way that all other girls had said yes - without knowing that he had used the same trick towards the other girls.
The role of Elin gave Eva Gram Schjoldager the opportunity to explore the theme of bullying, and later in life she visited elementary schools to talk about bullying based on the movie.
For the casting, a young Nils Malmros visited all the schools in Aarhus to look at 1400 children. He chose the ones who looked like the kids Malmros had been surrounded by in his second grade. His old class had materialized in a new form with seventeen look-alikes.