Five Heads of School have led SCEGGS since 1895:
- Miss Edith Badham (1895-1920)
- Miss Dorothy Wilkinson (1921-1947)
- Miss Barbara Chisholm OBE (1947-1977)
- Miss Diana Bowman AM (1978-1995)
- Ms Jenny Allum (1996 +)
Under their leadership, SCEGGS has expanded from a terrace house in 1895 to a campus incorporating the new Joan Freeman Science, Art and Technology Centre, the new libraries, a new Primary School, Senior Studies Centre, Performing Arts Centre, Sports Hall, Great Hall, and many other buildings containing attractive, functional classrooms surrounded by appropriate, appealing outdoor areas and playground spaces for students.