Almost one in five students in primary school last year were in classes of 30 or more, with six schools recorded as having classrooms with above 40 pupils.
An analysis of data published by the Department of Education on more than 22,700 mainstream classes in more than 3,100 primary schools across the State showed 19.8 per cent of all pupils were in classes almost twice as large as the average for most developed countries.
It revealed 45 per cent of all primary schools had at least one classroom with 30 pupils or more in the 2018-2019 school year.
The record class size in primary education last year was 42 pupils, which was recorded in three schools: Scoil Náisiúnta Róis, Taylor’s Hill, Galway; Bunscoil Phádraig Naofa, Tuam, Co Galway; and Scoil Naomh Cholmcille, Carndonagh, Co Donegal.
The school with the highest average class size in the country was Scoil Mobhí in Glasnevin, Dublin, which last year had an average of 31.9 pupils in each of its eight classrooms.
Despite large numbers of new teachers being recruited in recent years, many schools continue to experience difficulty in keeping class sizes at recommended levels.
According to the Organisation for Economic Co-operation and Development (OECD), the average class size in most developed countries is 21. There is no statutory limit here on the size of general classes, although a Department of Education circular in 1990 stated “appropriate learning experience is difficult to achieve when classes consisting of mainly four-year-old children exceeds 25”.
Overall, more than 109,600 out of 553,319 registered primary pupils in the recent school year were in overcrowded classes.
However, the Department of Education figures also highlighted how average class sizes nationally have been falling since 2015-2016, when they stood at 25.4 pupils per class.
They decreased further in the last school year to 24.3, down from 24.5 in 2017-2018, but are still relatively high by international standards. The lowest average recorded was 23.8 in 2008.