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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The boy was found unconscious and in cardiac arrest and was rushed to hospital where he died.
The victim, who was wearing her uniform at the time, was found knocking on doors nearly four hours after she was abducted.
There will be gales across Scotland and northern England this morning, but these will gradually ease through the afternoon.