At a low-key meeting at the weekend of its central executive committee, the ASTI voted to recommend rejection of the Government's offer on supervision.
Judging by past form, teachers are now likely to reject the €38-per-hour offer in the ballot on the issue scheduled for March 3rd-13th.
However, this will have little practical impact on schools, as the Government's contingency plan - which involved the use of external staff - will continue.
Last year 60 per cent of ASTI voters backed the supervision offer. But support for the scheme has cooled since the union realised that teachers would only be paid for hours actually delivered. They want teachers to be paid for making themselves available for supervision and substitution work.
The ASTI central executive voted by a two-to-one margin to recommend rejection of the supervision offer.
The mood at the meeting was described by one senior source as downbeat. "There is a sense that we are going through the motions. Everyone realises we have lost credibility with the public. It is time for a new strategy," he said.
Another senior executive figure said the organisation was battle-weary and tired.
The Minister for Education, Mr Dempsey, and school management groups have expressed their disappointment at the decision.
Mr George O'Callaghan of the Joint Managerial Body (JMB) said the contingency plan was now costing over €1 million per week.
The ASTI's 180-member central executive council also voted to compile an information bulletin on the benchmarking process. This will be distributed to all 17,000 members in the coming weeks.
ASTI opted out of the benchmarking process and left the ICTU at the outset of its pay campaign three years ago. However, some grassroots members are now anxious for the union to return to the Congress fold.
Several motions proposing a return to the ICTU have been tabled for the annual conference over Easter. The ASTI will also hear motions from delegates critical of the leadership of the union.
Some senior ASTI figures are concerned that there will be a low turnout for the second ballot on supervision.
One said that many members were "fed up" with ASTI and its various battles. "Many of these may not even bother to vote," a senior figure predicted.
The JMB said it was "disappointing that the significant progress that had been made by schools in implementing the new supervision and substitution arrangements at the outset of the term has now been halted by the ASTI decision to reballot members".
The body said it believed that the current scheme agreed in negotiations was "fair and flexible", and both met the needs of the schools and provided a paid system of supervision and substitution for teachers. The JMB stressed that "the offer is a good one and provides an opportunity for the payment of teachers for work which has been done on a voluntary, unpaid basis up to now".
School managers stressed that the scheme was voluntary.
The JMB said it had always maintained that supervision and substitution work should be paid, and that teachers should have the opportunity to be involved in this work.
"The offer from the Department of Education and Science acknowledges these principles."