In 1864 Reverend Crofts of the Glebe, Kilsallaghan, donated a piece of land for a nominal sum to facilitate the building of the first Kilcoskan National School. This was a one roomed, one teacher school which stood less than 500 meters from the current site in what today is a residential home. With stone steps leading up the outside gable wall, the living quarters for the school "master'' were above the single classroom. Initially about 20 pupils attended the school. In the 1930's the school was refitted for a second classroom.

By the early 1940's it was agreed that due mainly to overcrowding, a new school was needed. The Monks family donated a piece of land and the Parish Priest of the time Fr. Kevlihan organized for the building of the current school.

Mrs. Collins and the Headmistress Mrs. "Mag" Clinch did great fundraising work locally and in 1948 the building was ready for use. This remains the main Kilcoskan National School building that is still in use today. Over the years the school has also become associated with Blessed Francis Taylor and is in fact sometimes known as Francis Taylor National School. Born nearby in Swords circa 1550, Francis Taylor was elected Dublin's mayor in 1595. Later he was imprisoned for his Catholic faith, and died on 29 January 1621 while still in prison, after seven years of refusing to give up his religion in return for his freedom. Pope John Paul II beatified Francis Taylor on 27 September 1992.

In 2004 a large new classroom and reception area were added to Kilcoskan NS, again with the help of great local fundraising. Between 2004 and 2014 the school also used a number of prefabs as classrooms and learning spaces. In 2015 the school, Board and community were delighted to see the completion of a major school building project - involving the upgrading of all original classes, the addition of 2 new mainstream classrooms, 2 small group teaching rooms, a new meeting room and office and of course the addition of a fabulous state of the art facility for the teaching of children with Autism. All of these fabulous facilities encircle our super central "Green Room" / "Seomra Glas" where assemblies, displays and school productions are now held. The school now has 110 pupils approximately.

Through all the years of change and development in Kilcoskan National School we are happy and proud to have kept the friendly, caring, child-centered community spirit alive in our school. Kilcoskan National school is thriving and we are excited to be educating the young people of this great community for life in the 21st century.