She left the university in 1978, and became a mathematics teacher at Putney High School in London from 1978 to 1993. It was during this time that she wrote her books for young mathematicians. In 1993 she returned to German academia as a professor of mathematics education at the University of Erlangen–Nuremberg. She retired from Erlangen and moved to the University of Debrecen, in Hungary, in 2001, but died on 19 December 2001, shortly after starting her new position there. Cofman was the author of: