Strike action is last thing Northern Ireland teachers want, says INTO
The majority of teachers in Northern Ireland are to hold a half-day strike on Tuesday 21 February.
The UTU and INTO unions are to take action from midnight until 12:00 GMT and the NASUWT union has confirmed it will also take strike action.
It is expected many schools will close until midday, as most teachers in Northern Ireland are represented by those three unions.
Mark McTaggart from INTO told BBC News NI that teachers are taking the action reluctantly after years of stagnant pay.