Delegates at the three teachers' union conferences are set to vote on whether to ballot their members for industrial action.
It’s after the government changed the vaccine plan last week -- removing them as a priority category.
Following advice from the National Immunisation Advisory Council, Health Minister Stephen Donnelly revealed a new plan for the vaccine drive against Covid-19 last Tuesday.
After the medically vulnerable are inoculated, vaccine doses are now to be prioritised by age only.
It came as a shock to teachers who had been expecting all school staff to be among the first third of the population to receive a dose.
ASTI President Ann Piggott says it's not the last eight weeks before the summer term they're worried about.
Since yesterday the leadership of the ASTI, TUI and INTO have been working on the text of a motion aiming to hold the government to the original commitment.
They will all debate motions for industrial action at their national conferences this week.
Other issues featuring prominently on the conference agendas are reforms to the state exams, staffing levels, pay for younger teachers and class sizes.
TUI president Martin Marjoram says the pandemic has exposed a real shortages of substitutes -- and it's been harder for young teachers to stay in the job.
Any ballot on industrial action will have to be issued to teachers at their workplaces.
That means it's not likely to stop the remainder of students now attending class from home returning to their desks after the Easter break.