Delegates attending the ASTI annual convention in Killarney voted yesterday to ballot members on industrial action if the Department of Education and Science failed to agree a reduction in pupil-teacher ratios.
They are demanding a ratio of 15:1.
Delegates also called on parents to assist them in their quest for smaller classes.
Teachers reported that they found teaching large classes stressful and that it was detrimental to the quality of education of their students.
"This motion is not just a motion from a teacher perspective, it is a motion from a pupil perspective," argued a Donegal delegate, Mr Paul Fiorentini.
"I'm a rag and a bone and a hank of hair at the end of the day," said Ms Helen Breathnach, a Dublin delegate. "I'm exhausted teaching large classes, although I have never taught more than 30 in a class," she said. She said that to mark an honours Irish essay took 20 minutes. Marking essays for a class of 30 took her 10 hours.
Mr Noel Buckley, ASTI learning support convenor, said that a ratio of 15:1 did not mean classes of only 15 students. "In reality," he explained, "it means that there will be 25 students in a class. Currently class sizes range from 30 to 40, he said. "Surveys and research show that some 20 per cent of Irish pupils have some learning difficulty. For example a survey by the Departments of Health and Education shows that there are 15,000 pupils in Dublin with learning difficulties and 2,000 in Limerick. Only 45 cases of attention deficit disorder pupils are currently receiving treatment," he said.
Mr Buckley invited parents of children with learning disorder to join teachers in their campaign.
Ms Niamh Slattery, a delegate from Dublin North East, said she had been a part-time teacher for more than six years. She was one of a growing band of young teachers who lacked job security and recognition. It was "a ridiculously long apprenticeship", she said. If she tried to get a mortgage she would be laughed out of court.
Lowering the pupil teacher ratio would have huge benefits for teachers like her, she said. Of the 56 teachers in her school, 45 were permanent. If the profession wanted to continue to attract high-calibre people, then people in her situation had to be looked after.
A Sligo delegate, Ms Mary Duggan, said that teachers were doing their best but they couldn't compensate for overcrowded classrooms.
Mr Jim O'Brien, Navan, was applauded when he proposed that teachers tell the Minister that from September they would adhere to union guidelines.
Ms Bernadine O'Sullivan, ASTI president elect, told the delegates that after the pay issue this was the most important motion of the convention. "We have been talking about this for 15 or 20 years and in that time huge changes have taken place. Last year we had a very intensive campaign of lobbying politicians but it delivered nothing in terms of a reduction in the pupil-teacher ratio. The only imaginative effort the Department will recognise is industrial action."
"I think that together teachers and parents are a powerful combination. We should have a joint campaign," she said.
ASTI delegates also voted to negotiate a phased reduction in class contact hours to a maximum of 18 hours a week. They also agreed that a campaign of action would begin if no progress was made by January 2000.
Among the issues to be debated today are job-sharing, discrimination and child labour.