Until 1940, all young girls on the Leinster side of Athlone attended the Bower National school, Retreat road. The boys attended the Marist National school which was located in the building beside St. Mary’s church. These schools catered for children from ages 4 to 12 years.
In 1940 the Infant school was built in the Fair Green. It consisted of five classrooms. On 1st September 1941, Madame Dominic Teresa brought the young girls from first class, senior infants and junior infants to their new school. Three classes of little boys arrived down from the Marist school . There were 183 pupils in all. Athlone Woollen Mills had burnt down the previous November in 1940 and many of the children’s parents were out of work and very badly off.
In the late 1940s two extra classrooms were built into the original building as well as a block of toilets. In the mid 1950s, with the population of the town expanding rapidly, a second building with four classrooms was erected. In 1971, the third part of St Mary’s National School was built- a flat roofed building with five rooms. During the 1970s and 1980s, every classroom was full- five junior infant classes, five senior infant classes, five 1st classes and a special class. 500 plus infants attended the busy school.
After 1st class, the girls left the infant school and went to the Girl’s Senior National School on Retreat Road. The Bower Sisters came to teach in this school in 1890. In 1988 Sr. Ita Meares retired and Mrs. Ita Cunningham became the first lay principal.
After 1st class, the boys left the infant school to attend the Marist National School across the road. The present building was built in 1963. Br. Brian retired in 1994 and Mr John Martin became the first lay principal here.
Numbers were dropping in the town schools during the 1990s due to the expanding suburbs. There were empty classrooms in all buildings. Eventually in 1998 amalgamation took place. The staff of the three schools came together on two campuses- the infant school and the Marist National School. Ms Mary Daly and then Ms. Mgt. Naughton were principals of the new St Mary’s National School.