Our Lady's Secondary School
Monaghan
Key facts
- Mixed
- Pupils enrolled
- 883 larger than the median Irish post-primary school (585 pupils)
- Girls and boys
- 434 girls, 449 boys
- Ethos
- Catholic
- Teaching through Irish
- No subjects taught through Irish
- Roll number
- 64770M the Department of Education reference for this school
School details
Location
About
Our Lady’s Secondary School is a voluntary Catholic secondary school situated on a hilltop overlooking Castleblayney, Co. Monaghan. Operating under the trusteeship of CEIST and the traditions of the Sisters of Mercy, the school provides a holistic centre of development where each pupil is regarded as a unique individual. The ethos promotes a healthy, safe, stimulating and friendly environment characterised by mutual respect, cooperation and challenge, with a strong Christian foundation that encourages charity, inclusivity and understanding. The campus combines historic charm with modern facilities. Recent extensions house specialist classrooms, a biology laboratory, home economics rooms, construction studies and technical graphics suites, as well as two computer suites and a well‑equipped staff room. A dedicated library occupies the refurbished 1918 building, while a purpose‑built concert hall, opened by President Mary Robinson, and a gym support a vibrant programme of extracurricular activities, including sports clubs, art, and language groups. The school also offers three Special Needs classes, reflecting its commitment to inclusive education and the wellbeing of all learners.
History
The school’s origins date to 1905 when three Mercy sisters arrived in Castleblayney and established a primary school in 1912. In 1918 Scoil Mhuire Secondary School opened in the present Art Room building. A two‑storey building was added in 1962, providing boarding facilities until 1974. In 1971 Our Lady’s Secondary School was formed through the amalgamation of Scoil Mhuire and the boys’ St Mary’s Secondary School. Subsequent developments included prefabricated classrooms (1975), a gym (1979), GPA and additional classrooms (1980), and a major extension opened in September 1999 with new science, technology and computer facilities. A new concert hall was inaugurated in 1993, and throughout the 1990s the school introduced the Junior Certificate Schools Programme, Leaving Certificate Applied, Leaving Certificate Vocational, and the Transition Year Programme (1998). The school continues to build on its Mercy tradition and CEIST charter values.
Applying to Our Lady's Secondary School
For a September 2027 place, a school's formal admissions process cannot begin before 1 October 2026. The school sets its own opening and closing dates in its annual admission notice.
National term dates 2026/27
Irish schools follow a standardised school year, so these nationwide post-primary school dates apply broadly to Our Lady's Secondary School. Individual schools set their own discretionary closure days, confirm exact dates with the school.
- October Mid-Term Break: Mon 26 Oct – Fri 30 Oct 2026
- Christmas Holidays: Wed 23 Dec 2026 – Tue 5 Jan 2027
- February Mid-Term Break: Mon 15 Feb – Fri 19 Feb 2027 (primary schools: Thu 18 Feb – Fri 19 Feb 2027)
- Easter Holidays: Mon 22 Mar – Sun 4 Apr 2027
Primary schools close for the last two days of the February mid-term week and may use discretionary days to take the full week, so their break can be shorter than post-primary schools'.
Frequently asked questions about Our Lady's Secondary School
How many pupils attend Our Lady's Secondary School?
Our Lady's Secondary School has 883 pupils enrolled, 434 girls and 449 boys. That makes it larger than the median Irish post-primary school, which has 585 pupils.
Is Our Lady's Secondary School a DEIS school?
No. Our Lady's Secondary School is not part of DEIS, the Department of Education programme of additional supports for schools serving communities at risk of educational disadvantage. Not holding DEIS status says nothing about how good a school is, only about the profile of the community it serves.
What is the ethos of Our Lady's Secondary School?
Our Lady's Secondary School has a Catholic ethos. It is a mixed post-primary school.