Almost a third of teachers spent at least a working week of their Easter "break" on their jobs, a snap poll has suggested.
The survey by Tes shows that 30 per cent of those polled spent between five and nine days doing their job over the holidays. And another 2 per cent worked at least 10 days of the holiday.
It also reveals that the majority of respondents believe the situation is getting worse.
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Background: Why do teachers work more overtime?
The new figures show 54 per cent of teachers were working more over Easter than they did a year ago, while 60 per cent said they worked more than they had done five years ago.
One teacher warned: “It is a necessity if I’m to cope the next term. There is just no hope of getting all my marking and planning done in the term.”
Marking and planning was by far the most common reason given – by 52 per cent of the respondents, followed by administration (21 per cent) and GCSE revision (12 per cent).
Six per cent of teachers said they had worked during the holidays because of the demands of school leadership.
The majority of teachers (59 per cent) said they worked between one and four days over Easter.
Other reasons cited were revision for A levels and Sats, Ofsted preparation, classroom displays and helping with an Easter school.
The findings come amid rising concern about teacher workload.
Last month, the NASUWT teaching union general secretary Chris Keates said government recommendations to tackle workload needed to be given "some statutory force".
She told Tes that the Department for Education’s three working groups on workload had come up with “quite good recommendations, actually, that if they were implemented could make a difference”.
Many teachers responding to the survey this week told Tes they had felt compelled to work during the holidays.
One respondent said: “I don’t see any other option, otherwise the school won’t be ready for the children’s return.
"Also, Sats are still used to guide Ofsted with attainment rather than progress. As our children come at such a low entry level, they have a bigger journey to make so Easter School is essential.”
Another said: “It is becoming the norm. [There are] not enough hours in the week to meet expectations.”
And another respondent said they were working because “ridiculous Year 6 teaching is almost impossible with the targets we have been given”.
The snap poll has received 331 responses over the past week.