Soaring numbers of teachers are calling helplines for advice on how to cope after being “cyberbullied” on the internet by their pupils.

The Association of School and College Leaders (ASCL) said that it now receives a call every day from teachers who say they have become victims. The problem was unheard of just two years ago.

Pupils are scouring the internet looking for embarrassing photographs of them. They also use chatrooms and networking sites, such as Facebook or Bebo, to share incriminating material or make vicious accusations about their tutors.

Union leaders are urging their members to be cautious about content and ease of access to material they put on the internet. Many teachers have Facebook pages on which they share photographs of holidays or nights out with friends.

The caution comes after a teacher who allegedly appeared in a provocative advert was suspended from her job at an independent school, Stockport Grammar School. Her pupils found the advertisement, for construction workers’ clothes, on the internet. It shows three women simulating sex acts with three workers. One of them, allegedly the teacher, is shown apparently having sex on a desk. The video has been viewed thousands of times on a website.

It emerged this week that students at the University of Bradford used Facebook to criticise a lecturer.

They created a page entitled “Annie Smith is S***”, Times Higher Education reported. The webpage listed grievances about the woman along with a number of abusive comments. Dr Smith said: “Lecturers are finding that there is a big change in the way that students behave. They are becoming more aggressive.”

Bob Carstairs, assistant general secretary of the ASCL, assists with a helpline. He said: “One of the most commonly reported problems is pupils being extremely rude about teachers on the internet. The advice we give heads is to ignore it and get on with your life, unless the material is sexual or violent.”

One head teacher contacted the helpline after his pupils created a page on Bebo that said he became aroused by beating children. Husband and wife teachers had allegations about their sex life placed on a website by pupils.

Another teacher contacted her union after a disgruntled former boyfriend put intimate footage of them on the internet, which she did not know had been filmed. She became aware of this when her pupils found it and told her. A spokeswoman for the Association of Teachers and Lecturers said: “It made things very awkward with her pupils.”

A survey by the Teacher Support Network found 17 per cent of teachers had suffered cyberbullying. Pupils were responsible in more than a third of cases. A spokesman for the Department of Children, Schools and Families said: “We have issued clear guidance on cyberbullying. Teachers can now confiscate phones and control computer access and usage in the classroom.”

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