Stuart Adrian Organ (8 November 1951 – 15 February 2024) was a British actor, best known for his role as teacher Peter Robson on the television series Grange Hill. He appeared as the character for 15 years, from 1988 to 2003, across 260 episodes.

Organ was best known for his portrayal of the character Mr. Robson in the children's television drama Grange Hill. Organ portrayed the series' longest-serving teacher, arriving in 1988 as the new head of PE. In 1998 he finally landed the headmaster's job, but left the series in 2003 soon after production of Grange Hill transferred to Liverpool.

Prior to Grange Hill, Organ appeared as Kevin Cross in the Mersey TV soap opera Brookside, and played Bazin in the Doctor Who story Dragonfire in 1987. Thereafter, he appeared in a variety of roles on T.V., including Monk, a flasher who exposed himself to Anna and yet was defended by Miles in This Life; Richard Thornton, who stalked Acting D.I. Sam Nixon across a double episode special in The Bill; and later as D.I. Dixon in 2000, Leighton Peters, a top civil servant who was responsible for the downfall of Anthony Calf's regular in a double episode of Holby City and as solicitor Steve Morris in series 13, episode 14 of London's Burning.

Organ died on 15 February 2024, at the age of 72