Teacher unions say their members will consider strike action over the revised Covid-19 vaccine programme.
The Teachers' Union of Ireland (TUI) and the Association of Secondary Teachers (ASTI) are preparing emergency motions for discussion ahead of their annual conferences tomorrow.
It is believed the Irish National Teachers' Organisation (INTO) is doing the same.
Teachers had been due to receive vaccines as essential workers but the Government agreed last week to change the vaccination programme priority list to an age-based model.
Michael Gillespie, General Secretary of the TUI, says vaccinating teachers would ensure schools stay open.
"If you can vaccinate teachers, then you can protect the sustainable reopening of schools," he said.
"The Government have stated continuously that one of the things it wants to open up fully is schools. Well, if it wants to keep schools open, you vaccinate them."
The ASTI says teachers are angry at having been "totally discarded" in the Government's revised vaccination programme.
It will be put to members at their annual conferences this week.
President of the ASTI, Ann Piggott, says the Government needs to reverse the decision.
She said: "I'm not sure what the motion will actually entail or whether members will choose to pass it, but we're not going to pass a motion that will sort of mean we're going to express our sadness at what has happened and move on.
"Something bad has happened, teachers are annoyed. This decision has to be rescinded or changed in some way and we need to see action."