St Mary’s Anglican Girls’ School was founded when two private girls’ schools operating in West Perth amalgamated. The school opened on 14 September 1921 with the Rev C L Riley as Acting Principal. Later two other schools joined them.
Miss E Dannatt, Headmistress from 1923-1937, greatly influenced the early development of St Mary’s, and today she is remembered in the naming of Dannatt Hall and the Dannatt Bursary.
Following Miss Dannatt’s resignation, St Mary’s had a succession of Headmistresses: Miss K Carter (1938-1941), Miss B Hamilton (1942-1944), Mrs E Myles (1945-1956) and Mrs T Macdonald (1957-1965). It was during Mrs Macdonald’s period as Headmistress that the decision was made to move St Mary’s from West Perth to Karrinyup.
In 1964 a building appeal was launched to develop the present site in Karrinyup. Under the guidance of Mrs A Symington (1965-1982) St Mary’s operated in both West Perth and Karrinyup until 1970 when the whole school was finally situated in Karrinyup.
Mrs Audrey Jackson was appointed as Principal in 1983 (1983-1997) and continued the development of facilities with the establishment of the Education Support Unit, the development of the Drama and Music and Art Centres, and the completion of the Bedbrook Redenbach Science Laboratories. The new Junior School was opened in 1993 and the renovations to the Mathematics Teaching Centre were completed for the 1994 school year. The Audrey Jackson Learning Technologies Centre, including the refurbished library and new computer laboratories, was opened during 1996.
In April 1997 Mrs Lynne Thomson became the eighth Principal of the school. In 1998, Anne Symington House underwent refurbishment and renovation to convert St Mary's boarding facilities into first class accommodation. In September 1998, construction commenced on the Performing Arts Centre and on 17 March 2000 The Lady Wardle Performing Arts Centre was officially opened.
It was with great delight and excitement that St Mary's celebrated its 80th birthday in 2001. In 2003 construction commenced on the Lady Treatt Music and Dance Centre which opened in 2004.
The school’s eighty-fifth year saw significant development of the Junior School with the addition of the Margaret Field Hall, a new Pre-primary building, new classrooms and refurbishment of existing buildings to provide a new Maths/Science Laboratory and Learning Support Centre.
In 2005 the St Mary’s Anglican Girls’ School Foundation purchased a 100 acre property at Metricup in the heart of the Margaret River Wine Region for the school to develop a state of the art outdoor education facility. In May 2007 the building of St Mary’s at Metricup: A Centre for Learning and Leadership began. The Centre is due to open early in 2008 and St Mary’s will be the first all girls’ school in Western Australia to establish such a facility.