La Sainte Union Secondary School was a voluntary Catholic School run by the sister of La Sainte Union de Sacre Coeur, A Congregation founded in France , in 1826 to promote Christian education. La Sainte Union School , Banagher first opened its doors in 1863 in a house on Main Street . Many new buildings have been added especially in recent years. Originally boys and girls were accommodated in the boarding school. In 1927 the boys boarders transferred to the LSU convent in Killashee, Co Kildare. In 1974 the school again became co-educationally when the day boys enrolled.

St Rynagh’s CC, formerly known as Banagher Vocational School , opened in 1953. The school officially opened in mid October, by the then Minister for Education, Mr Sean Moylan. Forty students were enrolled under the guidance of the principal, Ms Elsie Naughton, RIP, who was highly respected and fondly remembered by all. St Rynagh’s has undergone many changes in appearance and facilities since its foundation including a major extension which was officially opened in 1986.

1999 the Department of Education and Science, rather than grant additional much needed accommodation to each school separately, requested that St Rynagh’s CC and La Sainte Union, secondary school consider amalgamating into one school which would cater for the needs of both on the one site. In 2001 the trustees of both schools agreed that in the best interests of the educational needs of the locality that the new community college should be built in Banagher. By November 2005 it was agreed that the state of the art a public-private partnership should be constructed on the La Sainte Union site, it will called Banagher College- Coláiste na Sionna.

The construction of the new school commenced during 2007 and was fully operational by 2010. Students will benefit from the experience and expertise of all staff working together to a common end – the full realisation of our Mission Statement.