St. Monica is one of the oldest schools in the Toronto Catholic District School Board with a history stretching over 87 years. In 1916, members of St. Monica Parish approached the Separate School Board to ask for a portable school on Broadway Avenue close to St. Monica Church. In 1916, the Ministry of Education lists two sisters of St. Joseph as having been the first teachers at St. Monica. In 1918, there were 138 pupils enrolled in the school. At some point in later years, by 1935 at the latest, the school came into the care of the Loretto Sisters. A permanent building was erected on the site by 1925, with additions in 1955, 1963, and 1966.
