A Dublin primary school has the highest average class size in the country.
Scoil Mobhí in Glasnevin had an average of 31.9 pupils in each of its eight classrooms last year.
Nationwide, one in five primary school students are being taught in classes of 30 or more.
The Department of Education recommends that class sizes don't exceed 25 students.
The biggest class size in primary education was 42, which was recorded in three schools - two in Galway and one in Donegal.
In Dublin, Scoil Mobhí in Glasnevin tops the list followed by both St Brigid's Boys NS in Foxrock and St Pius GNS in Terenure which have an average of 31.9 pupils in classrooms.
