Image copyright Thinkstock Image caption More than half of heads say parents' behaviour on social media is a concern

A primary school head teacher has revealed that she ended up on anti-depressants after parents used a closed group on Facebook to criticise her.

It was "a constant stream of complaint and comment about tiny issues, often out of context", she says.

More than half of the 1,188 head teachers who replied to a survey by schools management service The Key say parents' online behaviour is a problem.

And 15% say they have themselves suffered from negative behaviour.

Mary, not her real name, who started her headship 18 months ago and wants to remain anonymous, says there is criticism all the time.

"Some parents say the heart of the school has gone since I have taken over," she told the BBC. "It is bullying. All I am trying to do is improve their children's education.

"Before I started treatment for depression and anxiety, I felt paranoid and intimidated. It feels as if people are ganging up on you. A parent might make a simple comment and others might add comments without understanding the context.

"It gets out of hand and misinterpreted. I can't take the page down because it is not run by me and I don't feel I am in a position to defend myself."

Another primary head who responded to the online survey, said social media meant that "negative and inaccurate comments that would never be said face-to face are often posted by parents online".

Image copyright AndreyPopov Image caption Teachers are advised to avoid accepting social media requests

The NASUWT teachers' union says says the online bullying of teachers by pupils and parents is a growing trend.

One secondary teacher in her 20s from the Midlands told the union's magazine she had been harassed online by pupils.

"It's constant Facebook requests, Instagram requests and eventually somebody decided to send me a message to say a few boys thought I was sexy and that I was fit."

She says the comments, which spilled into the classroom, made her feel extremely uncomfortable before senior management at the school intervened.

John Collier, head of teacher training at Britannia Teaching School Alliance in the West Midlands, said problems were happening "more than you think".

He advises new teachers to be very careful with their social media privacy settings and to avoid accepting friend requests from pupils. recent pupils or even parents.

"If you are visible you are vulnerable not only to parents being able to contact you online, but the pupils themselves."

'Wave of positivity'

But Andrew Teale, head of St Paul's Church of England Primary School in Hereford, said that, properly used, social media can be an "enormously positive force" in schools.

When St Paul's posts pictures on the school's official Facebook and Twitter accounts, parents "lap it up" and it generates "a wave of positivity", said Mr Teale.

He says that blaming social media for bullying "is a bit like blaming a pen for a nasty letter".

"What we don't want is for teachers to run away from social media."

However, he says teachers should be aware of the negative side and know that they can contact their line managers if there is a problem.

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