Anachronisms: The locker room at the school has a passive Infra red detector clearly visible over one of the doors more recently used for intruder alarm systems. This type of device would not have been available until the early 1990s.
Anachronisms: In the montage scene in the library, at least two books, Michael Burleigh's "The Third Reich" (2001) and Alan Bullock's "Hitler and Stalin: Parallel Lives" (1991), are visible, neither of which had been published in 1983/84 when the film was set.
Anachronisms: The first time we see Hector giving a lift to one of the pupils on his motorbike, they drive past a house with a satellite dish on the wall. Satellite TV did not exist in the UK in 1983.
Anachronisms: The lollipop lady that reports Hector to the headmaster carries a sign that carries the international symbol for children, which has only recently started replacing the old sign that stated "STOP CHILDREN" - which would have been the sign used in 1983.
Factual errors: At the start of the film several school subjects are mentioned, including Media Studies. Media Studies is a relatively new subject that certainly wouldn't have been taught in provincial Sheffield in 1983.
Anachronisms: In the staff room when Hector says 'French Kiss' to the games master he is brandishing a copy of the Racing Post, however the Racing Post wasn't launched until 1986, three years after the year the film was set.