George A. Cooper (born 7th March, 1925) is a British actor perhaps best known for his long-running role as grumpy school caretaker Mr. Griffiths in Grange Hill. On Coronation Street he had a recurring role as Willie Piggott between 1964 and 1971 in between which he also appeared in Street spin-off Pardon the Expression in 1966. George's other credits include Doctor Who, Z Cars, The Avengers, The New Avengers, The Saint, Randall & Hopkirk (Deceased), Steptoe And Son, Some Mothers Do `Ave `Em and Billy Liar.