From 1940–41 Jessel worked at Oxford House, London. She enlisted into the Auxiliary Territorial Service, serving from 1941–43. She was a teacher at William Temple College from 1956–62. In 1965 she had published 'Owen of Uppingham'. She worked as a lecturer at Plater College, in Oxford from 1968–84.[3]
^‘JESSEL, Dame Penelope’, Who Was Who, A & C Black, an imprint of Bloomsbury Publishing plc, 1920–2015; online edn, Oxford University Press, 2014 ; online edn, April 2014 accessed 20 February 2015
^‘JESSEL, Dame Penelope’, Who Was Who, A & C Black, an imprint of Bloomsbury Publishing plc, 1920–2015; online edn, Oxford University Press, 2014 ; online edn, April 2014 accessed 20 February 2015
^‘JESSEL, Dame Penelope’, Who Was Who, A & C Black, an imprint of Bloomsbury Publishing plc, 1920–2015; online edn, Oxford University Press, 2014 ; online edn, April 2014 accessed 20 Feb 2015