The role of Miss Fritton was written for Margaret Rutherford; Alastair Sim took over the role when her services could not be secured.
The school motto, written under the silver cup stands, is "In flagrante delicto", Latin for "a burning offense". However, it was commonly used in British divorce cases as a euphemism for caught in the act of sex. It would, of course, hardly be the motto of a girls' school.
The third most successful film at the British box office for 1954.
After his 1st meeting with Millicent Fritton, Clarry Fritton pulls a 1/3rd pint of milk from his briefcase when he sits in his car. Children were given free milk at this time in this size bottle - the inference is that Clarry stole it on leaving the school.
The conversation between Miss Anderson ( played by Vivien Wood ) and The Sultan of Makyad ( played by Eric Pohlmann ) in the opening scenes about the schooling in England of his daughter Fatima ( played by Lorna Henderson ) establishes that St Trinians is located in Barchester - the fictional English county created by Anthony Trollope in his series of Chronicles of Barchester novels.
Ronald Searle: The cartoonist who invented St Trinians, appears as a parent in the scene in Miss Fritton's office directly after the race. He is the one with the beard. His wife Kaye Webb also appears in the same scene.