The film's alternative title S.W.A.L.K. is a common British abbreviation for Sealed With A Loving Kiss, a phrase that lovers write on the envelope of love letters to each other.
Jack Wild was playing an 12-year-old, despite being 17 at the time of filming in the early summer of 1970.
Renowned filmmakers such as Alejandro González Iñárritu and Wes Anderson are proclaimed fans of the film. Iñárritu stated that it was one of the first films that created a huge impact on him when he first saw it as a child.
Alan Parker spent several months visiting schools in London and tape recording conversations with the children about their experiences and thoughts before writing the script. According to producer, David Puttnam, "...large chunks of the film were lifted directly from the children's ideas", as well as Parker and Puttnam's own childhoods.
The Highmaster's House on Hammersmith Road near the junction of Colet Gardens, used as a location for the school that Melody, Daniel and Ornshaw attend, is now (2019) a hotel called St Paul's Hotel, with a restaurant and bar called The Melody, a reference to this film.