Secondary schools on the Island are on average almost five teachers short.
In the House of Keys yesterday the Department of Education and Children published figures about vacant teaching posts.
It was in response to a question for written answer from Garff MHK Daphne Caine - she wanted to know how many posts were unfilled in primary and secondary schools, and how teaching jobs are being filled by supply teachers.
Minister Graham Cregeen revealed there are currently 24 unfilled teaching jobs in the Island's five secondary schools.
In his answer Mr Cregeen said in the Island's 32 primary schools there are another 13 vacancies and a further four full-time equivalent posts being filled by supply teachers.
But the figures show the problem is worse in secondary schools with 24 vacancies and more than 12 staff members teaching their second subjects.
Mr Cregeen says all those teaching their second subjects are qualified to do so.
His answer shows science and maths are hardest-hit, with a total of seven secondary school posts being filled by teachers who specialise in a different subject.