The band at the dance, The Mindbenders, were the original backing band for Wayne Fontana. Wayne Fontana and the Mindbenders had a hit with "Game of Love" while the Mindbenders had a hit with "Groovy Kind of Love". Eric Stewart from the Mindbenders went onto greater success as part of 10CC.
The producers sought permission to film in the British Museum for the outing sequence. However, they were denied this only a few days prior to filming, although stills photography was permitted. Stills photographers Laurie Ridley and Dennis C. Stone were given a free hand, following the cast throughout the Museum, creating the classic montage sequence in the movie.
The London bus, LLU 829, which appears in several sequences at the start of the film and in some later sequences, still survives today as a preserved vintage vehicle, and can be seen at the East Anglia Transport Museum, Carlton Colville, Lowestoft, England.
Sidney Poitier really IS "Sir." He was appointed an Knight Commander of the Order of the British Empire in 1974. (He's a native of the Bahamas, part of the Commonwealth of British Nations.) This is not an honorary award. He is entitled to be known as Sir Sidney Poitier, but does not use it himself.
When the students tell him he's like them, art imitates life. Sir Sidney was sent to the United States to live with his brother at age 15 (the age of the students) as he was getting into too much trouble at home in Nassau. Sir Sidney also knew what it was like to be young, poor, uneducated, and unemployed, after being in trouble at school. At 16, he headed for New York City and even took to sleeping in the bus terminal while homeless.
Lulu's title song, "To Sir With Love" finished the year number one on the Billboard Top One-hundred List. "Talk to the Animals" won the Academy Award and none of the songs nominated for Best Original Song Oscars broke into the year '67 top 100. Only the nominated "The Look of Love" was number 36 in the following year's Billboard List.
Based on the semi-autobiographical novel by E.R. Braithwaite and his experiences teaching in a tough secondary school in a poor area of London, the films portrayal of Braithwaite's character may not have been entirely accurate. After the film was made some former pupils of Braithwaite's claimed that, in reality, he was a stern and tough disciplinarian who often used corporal punishment in class and was far from the sympathetic portrayal by Sidney Poitier.
As part of SNL's closing act for its January 21, 2017 show, cast members Cecily Strong and Sasheer Zamata sang "To Sir With Love" as a tribute to former President Barack Obama. Considering that Obama like Poiter's character in the film came from an island, was at times made to feel out of place by half of society and had to deal with unruly and undisciplined people both school children and adults, the song was a fitting homage.