Each year applications for entry to the certificate examinations are received and accepted in the case of individual prisoners who are following courses of study in prison.
There are two institutions, one in Galway and one in Mayo, which do not hold official recognition as post-primary schools but whose students are accepted for entry to the certificate examinations as "school" candidates.
Individual school candidates who have followed a course of study privately in a subject (e.g. music, art, a foreign language) are from time to time allowed to sit for that subject in the certificate examinations.