Moves to allay concerns over the pace and scale of changes to the Junior Cert have not gone far enough for teachers.
The Department of Education has announced a slowing down of the reform plan and a range of extra resources and other measures designed to ease the transition.
But the two second-level teacher unions have responded with "grave disappointment" and warned that they may ballot members on non-cooperation with the changes.
However, school managers have welcomed the supports.
The reform will involve a radical change in teaching and learning, with continuous assessment of students by teachers instead of traditional third-year June exams, for a new Junior Cycle Student Award (JCSA), issued by schools. The process is due to start next September with the introduction of a new English syllabus for first years, while other changes will be phased in over a number of years.
A Junior Cycle Working Group, established to address the concerns of teacher and school managers, met for the first time yesterday.
At the meeting, Department of Education officials presented a range of concessions, including stretching the end date for full transition to the new system from 2020 to 2022.
And instead of introducing revised syllabi in three subjects -- Irish, business and science in 2015, as originally planned -- only one subject, science, will change that year.
Among the other concessions announced at the meeting are an increase in teacher training and planning time for schools to assist in the transition.
The department also sought to address fears that the change will affect quality and lead to variations in standards between schools, by announcing that the new award will carry a Department of Education logo.
The dialogue about change is ongoing and sub-groups of the working party will meet next week to consider other issues.
Welcoming the new measures, Ferdia Kelly of the Joint Managerial Body (JMB), representing managers in about two thirds of schools, said the minister had "clearly been listening and although in school terms September is very close, we now have a much more realistic set of tools to get on with the job".
Michael Moriarty, general secretary of the Education and Training Boards Ireland (ETBI) -- formerly the VECs -- said "the minister and his department were to be congratulated" on the extent to which they listened. "Now, hopefully, all schools, teachers and students can move forward together to make junior cycle education the most rewarding experience possible," he said.
However, in a joint statement, the Association of Secondary Teachers, Ireland (ASTI) and the Teachers' Union of Ireland (TUI) said that the meeting did not involve genuine engagement on the issues of most concern to second-level teachers.
The executive bodies of the TUI and ASTI will now decide whether to ballot members on non-cooperation with the implementation of the changes.
TUI general secretary John MacGabhann said key questions on standards, capacity and equity which they had repeatedly posed were not satisfactorily answered.
"Even at this late stage, there remain more questions than answers and this is completely unacceptable," he said.