In 1887, Father Kenneth McDonald, pastor of the parish in Mabou, Nova Scotia, approached the Congrégation de Notre-Dame and expressed the desire that his parish have a Catholic School like the academy the sisters founded in neighbouring Port Hood. Father McDonald convinced the General Council of the Congregation to send sisters to teach at Saint Joseph Convent. In this context, in September of the same year, Sister Sainte-Béatrice (Mary Catherine Purcell), founding superior, and Sister Sainte-Suzanne (Marie Sophie Hicks) arrived in Mabou and moved into the convent which opened its doors on November 9. At that time, Saint Joseph Convent had two classes for girls and one for boys, for which a lay teacher was responsible. It had only twenty-nine students, of which eight were boarders. However, as early as 1888, many children from neighbouring towns registered at the convent, which was quickly gaining in popularity. The subjects that were taught were quite diverse; the students learned art, music, domestic science, agriculture and Gaelic culture. By 1928, a Grade 12 class was added. Also, in the school’s early years, several Saint Joseph Convent graduates chose to enter religious life.

In 1947, because of increasing demand and limited space, the business classes had to be transferred to Cameron House, located on the convent property. There were eighteen teaching sisters and more than four hundred fifty students. With continued growth, a new convent was built in 1950 with its inauguration being held on October 28, 1952. The size of this new building allowed regional events to take place, such as folk music concerts, agricultural meetings and award ceremonies. This new building served as both a boarding house for students and as a residence for the sisters. On June 14, 1954, an Institut familial (Domestic sciences school) was created. Because of the closure of many of the smaller local schools in neighbouring rural villages, it was decided that a Primary to Grade 12 Consolidated high school be built in Mabou. This establishment replaced the original Saint Joseph Convent school which was demolished in 1964.

The sisters of the Congrégation de Notre-Dame continued to administer both the school and the convent until 1966, when a lay person replaced the superior as school director. The sisters continued to receive boarders until September 1979. Many of the sisters taught at Mabou Consolidated School as well as at other primary schools in the region. They also administered Saint Joseph Renewal Centre, in addition to creating support groups for the sick and for people in need. They established literacy programmes and organized activities for the high school students, who they continued to teach until 1994.

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After being put up for sale in 2018, Colaisde na Gàidhlig | The Gaelic College based out of St. Ann's, Cape Breton assumed ownership.