On the 23rd of May 1861, four Presentation Sisters left their convent in Galway to found a Convent in Oranmore at the request of the Bishop, Most Rev. Dr. McEvilly. A sum of money was donated by Councillor John Blake of Galway for this purpose. Two of his sisters were members of the Order.Their first Convent was locally known as the ‘Hotel’ near the present Moorings Restaurant, while an out-building was converted into a college.
On the 18th July 1869, with the permission of Most Rev. Dr. Carr, the Sisters moved into the Parochial House of the then Parish Priest, Fr. R. Quinn, which was purchased for the sum of £600. The building of the old National College began in October 1886, and three years later the new convent was built adjoining the Parochial House. In 1916, a hall was built on the convent grounds to cater for Home Economics classes for the local girls. This became the first Secondary College when blessed by Rev. Michael Browne on the 27th August, 1946, the feast of St. Joseph Calasanctius.
The following year a Boarding College for girls was opened, and due to the increased demand for places, a major extension was erected in 1963 under the leadership of Mother Columba Heaney. In 1973, with permission from Dr. Browne, the college enrolled boys for the first time. This led to the building of a new wing, incorporating a Woodwork room. From 1987 onwards the college no longer catered for boarders, and the dormitories and refectories were converted into Science Laboratories and classrooms.
In 1994, when the Sisters decided to withdraw from the teaching staff, the convent was vacated and a lay Principal appointed. The school remained under the trusteeship of the Presentation Sisters until 2008, when trusteeship was transferred to CEIST (Catholic Education, An Irish Schools Trust). In 2001, the Department of Education and Science sanctioned new “state of the art” school buildings. The buildings include a Sports Hall, Library, Oratory, 4 Science Laboratories, 2 Home Economics Rooms, Art Room, Language Laboratory, Computer Laboratory, Woodwork and Construction Rooms, Technical Graphics Room, Social Studies Rooms, Guidance Suite, Music Rooms etc., with a greatly enhanced General Purpose Area.
These buildings were officially opened by the Minister for Education & Science in 2006. Calasanctius College is a co-educational school, which caters for the needs of the local community, with an enrolement of over 700 students. The students come from Oranmore and surrounding areas. They come from varied backgrounds, both socially and economically. The majority of students carry on to third-level education.