The school prides itself in spanning Primary Education in Roscommon town through an entire Century 1902 – 2002 and into the future.
The Sisters of Mercy arrived in Roscommon from Limerick in 1853 almost 150 years ago. They resided in a building in Church Street (now AIB) and taught in an old school in Chapel Lane from an old church in Penal times which had only an earthen floor.
It took several years before a suitable site was available on which to build a convent and a school. In 1861 a new Convent with an adjoining school of cut stone was opened. Towards the close of the century it became obvious that the school could not accommodate the increasing population of school going pupils in the town.
A three storey new building was constructed and this building was intended to afford room for an Elementary school and a full course of instruction under the Technical Education Act. A Special room was set aside for the teaching of lace making.
In 1929 the Secondary School was opened, and four rooms on the top storey of the Primary were occupied by the Secondary school.
The situation continued until a new secondary school was built in 1963. On 1st April 1964 work commenced on the reconstruction of the Primary school. The architect was Mrs. Mary O’ Carroll, Roscommon and the contractor was Mr. Owen Dervin, Roscommon. The top storey of the former three storey building was demolished. A single storey Kindergarten wing was added to the remaining section of the old school. The reconstructed building contained classrooms, cloakrooms, staff room, library, home economics room and a fine assembly hall. The school was blessed and reopened by the Very Rev. Canon Hanley.
As the seventies were coming to an end a need for more classrooms arose as the town’s population had grown and in the early eighties the number of children on roll reached an all time high of almost 500 children.
Another wing was added at ground floor level containing more classrooms, toilet facilities, a new staff room and a room specially adapted for traveller children ( this is no longer used for this purpose).