Tobias has the album "Zenyatta Mondatta" by The Police in his room, an album that was released on the 3rd October 1980, while the scene is set on the 1st August 1980.
In Tobias' room a book about the moon from the "What is What"-series (Was ist was) is visible. That book came out in 1982 but the movie is set in 1980.