Home · By area · Release notes. Enrolment by planning area, local authority, school patron, county.

ST MARYS SCHOOL

Roll number: 18411U Greenhills Road, Tallaght, Dublin 24

School details

Address: Greenhills Road, Tallaght, Dublin 24 (D24K248)
Email: [email protected]
Phone: 014515387
Principal: Shane Cadigan
Ethos: Catholic
DEIS: N
Irish classification: No subjects through Irish
Gaeltacht: N
Island: N
Local authority: South Dublin County Council
School patron: Archbishop of Dublin
School type: Ordinary
School level: All-Through School
Planning area: Tallaght

Class size history

Mainstream class group data is shown separately from standard/year-group enrolment data. The source does not identify which standard/year group each class group belongs to.

Average class size

24.93

2025/26

Mainstream classes

2025/26

Largest class group

2025/26

Classes with 30+ pupils

2025/26

Class group metrics trend

Class group metrics by year

Year	Mainstream class pupils	Mainstream classes	Average class size	Largest class	Classes 30+
2006/07	247	11	22.45	28	0
2007/08	270	13	20.77	26	0
2008/09	300	14	21.43	28	0
2009/10	293	14	20.93	27	0
2010/11	318	14	22.71	28	0
2011/12	337	15	22.47	28	0
2012/13	364	15	24.27	29	0
2013/14	363	13	27.92	33	4
2014/15	387	14	27.64	33	5
2015/16	384	14	27.43	33	2
2016/17	375	14	26.79	31	3
2017/18	364	14	26.00	33	3
2019/20	341	13	26.23	30	4
2020/21	315	13	24.23	29	0
2021/22	314	12	26.17	28	0
2022/23	313	13	24.08	28	0
2023/24	307	13	23.62	28	0
2024/25	323	13	24.85	28	0
2025/26	349	14	24.93	27	0

Data highlights

Key numbers to spot outliers or notable changes.

Biggest gain in a single year: 1976/77: 370 in 1975/76 → 434, +64 pupils.
Biggest loss in a single year: 1993/94: 488 in 1983/84 → 279, -209 pupils.
Largest single-class increase: 5th Class in 2025/26 (22 → 55, +33).
Largest single-class decrease: Senior Infants in 2021/22 (55 → 28, -27).
Largest cohort-step gain: 4th → 5th in 2025/26 (51 → 55, +4).
Largest cohort-step loss: JI → SI in 2024/25 (45 → 40, -5).
Overall: 511 (1974/75) → 349 (2025/26), -162.

Summary statistics (class-level data)

Min / max / mean enrolment per class across the available final by-standard years.

Class	Min	Max	Mean	Years
Junior Infants	28	53	45.3	6
Senior Infants	28	55	46.2	6
1st Class	19	52	40.0	6
2nd Class	21	55	38.5	6
3rd Class	20	54	36.0	6
4th Class	20	52	35.2	6
5th Class	22	55	40.2	6
6th Class	24	51	38.8	6
Total	265	511	345.3	43

Total enrolment over time

Total and gender trends use historical records where available. Class-level data starts in 2020/21.

Enrolment by gender over time

Enrolment by class over time

Cohort progression

Base cohort:

Track how each cohort (pupils who were in the same class in the same year) progresses through the school. Each step shows the count; the number between steps is the net change (pupils gained minus pupils lost).

Cohort 2020/21

JI 2020/21 28

SI 2021/22 28

1st 2022/23 28

-3

2nd 2023/24 25

3rd 2024/25 28

-2

4th 2025/26 26

Cohort 2021/22

JI 2021/22 50

SI 2022/23 51

1st 2023/24 52

2nd 2024/25 55

-1

3rd 2025/26 54

Cohort 2022/23

JI 2022/23 53

-1

SI 2023/24 52

1st 2024/25 52

2nd 2025/26 54

Cohort 2023/24

JI 2023/24 45

-5

SI 2024/25 40

-1

1st 2025/26 39

Cohort 2024/25

JI 2024/25 51

SI 2025/26 51

Cohort 2025/26

JI 2025/26 45

Raw data by year

Year	Female	Male	JI	SI	1st	2nd	3rd	4th	5th	6th	Total
1974/75	–	511	–	–	–	–	–	–	–	–	511
1975/76	–	–	–	–	–	–	–	–	–	–	370
1976/77	327	107	–	–	–	–	–	–	–	–	434
1977/78	311	146	–	–	–	–	–	–	–	–	457
1978/79	–	–	–	–	–	–	–	–	–	–	458
1979/80	279	185	–	–	–	–	–	–	–	–	464
1980/81	273	208	–	–	–	–	–	–	–	–	481
1981/82	248	222	–	–	–	–	–	–	–	–	470
1982/83	233	241	–	–	–	–	–	–	–	–	474
1983/84	241	247	–	–	–	–	–	–	–	–	488
1993/94	122	157	–	–	–	–	–	–	–	–	279
1994/95	128	150	–	–	–	–	–	–	–	–	278
1995/96	128	157	–	–	–	–	–	–	–	–	285
1996/97	125	144	–	–	–	–	–	–	–	–	269
1997/98	124	146	–	–	–	–	–	–	–	–	270
1998/99	121	145	–	–	–	–	–	–	–	–	266
1999/00	121	145	–	–	–	–	–	–	–	–	266
2000/01	120	145	–	–	–	–	–	–	–	–	265
2001/02	119	156	–	–	–	–	–	–	–	–	275
2002/03	121	155	–	–	–	–	–	–	–	–	276
2003/04	121	146	–	–	–	–	–	–	–	–	267
2004/05	123	148	–	–	–	–	–	–	–	–	271
2005/06	122	154	–	–	–	–	–	–	–	–	276
2006/07	121	146	–	–	–	–	–	–	–	–	267
2007/08	131	162	–	–	–	–	–	–	–	–	293
2008/09	145	175	–	–	–	–	–	–	–	–	320
2009/10	136	176	–	–	–	–	–	–	–	–	312
2010/11	143	189	–	–	–	–	–	–	–	–	332
2011/12	152	185	–	–	–	–	–	–	–	–	337
2012/13	181	183	–	–	–	–	–	–	–	–	364
2013/14	188	175	–	–	–	–	–	–	–	–	363
2014/15	194	193	–	–	–	–	–	–	–	–	387
2015/16	194	190	–	–	–	–	–	–	–	–	384
2016/17	192	183	–	–	–	–	–	–	–	–	375
2017/18	192	172	–	–	–	–	–	–	–	–	364
2018/19	170	167	–	–	–	–	–	–	–	–	337
2019/20	164	177	–	–	–	–	–	–	–	–	341
2020/21	146	169	28	55	19	28	37	52	50	46	315
2021/22	144	170	50	28	50	21	27	34	54	50	314
2022/23	142	171	53	51	28	48	20	28	34	51	313
2023/24	142	165	45	52	52	25	50	20	26	37	307
2024/25	151	172	51	40	52	55	28	51	22	24	323
2025/26	163	186	45	51	39	54	54	26	55	25	349