Jan Mark was born in Welwyn, Herefordshire. After moving in and around London, she moved to Ashford, Kent, starting school at the age of eight years. She won the second prize, when she was 15 years old, in a literary competition organised by the Daily Mirror. She was discouraged from reading English at university by a teacher and she instead studied design. After completing a national diploma in design at Canterbury College of Art she taught art and English at Southfields School, Gravesend. She became a full-time writer in 1974 at the age of 33 years. Her first novel, Thunder and Lightnings, won the Kestrel/Guardian prize for a children’s novel written by a previously unpublished writer. She won the Carnegie Medal (Britain’s foremost children’s literary award) in 1977, and again in 1984, for Handles.