The number of teachers facing abuse on social media has more than doubled in the past year, according to figures
This is up from 21 per cent in 2014.
48 per cent said the remarks were posted by pupils, with 40 per cent saying parents were behind the comments.
NASUWT general secretary Chris Keates said: “It is deeply worrying to see that the abuse of teachers has risen by such a huge margin this year.
“Equally concerning is that it appears that more parents are the perpetrators of the abuse.”
The study found that school staff are being confronted with sexist, racist and homophobic remarks, as well as offensive comments about their appearance, competence in the classroom and malicious slurs.
Among the examples published in the report include the case of a student uploading a teacher’s photo and then, along with classmates, writing the word “b****” underneath.
Another teacher said they were harassed for nine months by students who sent sexually explicit messages and set up a fake social media account in their name.
Mrs Keates added: “The vile, insulting and personal comments are taking their toll on teachers’ health and wellbeing and undermining their confidence to do their job.
“Many teachers tell us that they suspect they are being abused online but dare not look, for fear they could never walk into their school again to have to face their abusers.
NASUWT has called for the next government to take the issue seriously and to require schools to have a zero-tolerance policy and use all sanctions available to address abuse of staff.
Last month a report by Her Majesty’s Inspectorate of Constabulary for England and Wales showed that many parents resort to calling the police to deal with their disruptive children.
It cited cases where mums and dads felt the need to demand that officers come to their houses to sort out a situation that was out of control.
Teaching children manners and etiquette is a vital role as a parent but can equally be very hard.
Many children are often influenced by peers which can also reflect in their behaviour.
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