NASUWT General secretary Chris Keates said unions were trying to keep the action "pupil and parent friendly", such as cutting down on paperwork.
But she warned the position could change, especially after a report from the teachers' pay review body later this month.
A teacher with six years experience has lost £5,500 through a pay freeze and pension changes, while those in the job for two years had lost £3,500, she said:
Teacher morale is at an all-time low and our research shows that over half are seriously considering leaving the profession.
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Festival deaths and Northern Ireland abortion reform lead the papers.
Georgia Jones, 18, and Tommy Cowan, 20, were named locally as the pair who died after being taken ill at the Portsmouth event.
Targets for recycled and recyclable packaging should also be brought in to encourage firms to ‘harvest’ waste from consumers.