The school has Gaelic football, camogie and athletics teams. Basketball is a very successful sport in the school also. Camogie is another popular sport in the school and the teams traditionally compete at U/16 and U/18 at B-League levels within Leinster. In 2011 the Ladies B U/18 Gaelic football team won the Inter-Schools All-Ireland Cup. Basketball is a very big sport in school, shadowing their brother school colaiste eoin, who boost two remarkable teams, mainly though their B team who have had quite a fantastic session to this date.
History
In 1968 the Christian Brothers allocated land from its land part of the St. Helen's, Booterstown for the building of two schools, a girls school, Coláiste Íosagáin was established in 1971, under the control of the Sisters of Mercy, and boys schoolColáiste Eoin under the control of the Christian Brothers. In 1983 President Hillery opened the new Coláiste Íosagáin school.
New buildings
Early in the 1990s it was deemed that the school's existing single storey buildings, built in the 1970s, were far too small to accommodate the rapid growth and expansion of both Coláiste Eoin and Íosagáin. It was decided that the school would require both a new classroom block and a sports hall/auditorium. The project, however, experienced difficulties from the outset due to a lack of funds. It took many years of collecting voluntary donations from parents and other members of the public for the project to even reach the planning stage. A second barrier was posed by the fact that additional accommodation could only be placed in a constricted rear area of the site, because the existing grass, Gaelic pitch to the south of this site was sacrosanct. This restricted site condition caused the new building to be formed into two shared elements: a four storey academic block, and a Sports Hall with performance space. Despite these difficulties, building finally commenced in 2001, of a Grafton Architects designed structure that met with all the schools requirements. The project was completed in 2003 and has since won a prestigious award at the Royal Institute of the Architects of Ireland Awards 2004. Work recently went underway for a new building to be built on the far-side of Coláiste Íosagáin's main building, on a small side section of the school grass pitch in summer of 2013. The building consists of new classrooms, new changing rooms and chiefly, a school oratory. The building was completed in early December 2013 and is named 'Aireagal', because the main principle of the building is to provide an oratory for the students. This building completes the refurbishment of the school, and also means that no more classes are held in prefabricated buildings.
