St. Mary School was founded on September 11, 1871, by the Sisters of the Immaculate Heart of Mary. In 1888, the order left, but the school remained open under the direction of Katherine Murphy. In 1890, three Presentation sisters from Fitchburg, Massachusetts assumed the administration of the school at the invitation of Bishop Mora of the Monterey-Los Angeles Diocese.
In 1918, the Presentation Sisters of San Francisco amalgamated with the original community and continued until 1981 when an all-lay faculty replaced them. In 1987, Sr. Bobbi Green, PBVM, a St. Mary School alumnus, returned to teach, officially retired in 2021, and still comes by to enrich the lives of students as a volunteer. The present school building was opened in September, 1953, after being rebuilt after a devastating fire. A primary wing was added in 1973, a computer lab was installed in 1990, and most recently, a science lab was built and dedicated in 2006.
Our commitment to quality Catholic education has continued to grow as evidenced in our recent improvements. These include the addition of a science lab building; refurbishing the school building and gym; updating technology with mobile labs, computers, and permanently mounted classroom projectors; expanding the PE, music, art, Spanish enrichment, and sports programs; updating the curriculum and library; and promoting staff development.