Almost one in 10 teachers in England have been sexually harassed by a pupil, while several had "upskirt" images taken of them in the workplace, a "deeply disturbing" examination of life in the classroom has suggested.
A survey of teaching staff shows four-fifths (81%) felt they had suffered sexual harassment or bullying in the workplace since entering the profession, according to research by the NASUWT union.
Three in 10 (30%) said they had been subjected to unwanted touching, while two thirds (67%) claimed to have received inappropriate comments about their appearance.
More than half (51%) of the 1,290 people surveyed said they had received inappropriate comments about sex, while one fifth (21%) said they had been sexually propositioned.
Some 3% said they had been the victim of upskirting at work - the cruel craze of taking photographs or videos of a victim's groin area from beneath their clothing - or had images taken down their top.
Chris Keates, NASUWT general secretary, said: "Schools should be places of safety, yet research undertaken by the NASUWT is showing us that too often teachers are being exposed to sexualised comments and abuse from colleagues, managers, parents and pupils.
"The NASUWT will have no hesitation in taking action in schools where sexual harassment and bullying occur and employers fail to operate a zero-tolerance approach.
"While the scale of the sexual harassment is deeply disturbing, equally disturbing is the scale of the failure to act on the incidents that were reported."
The figures show 8% of teachers surveyed claim they were sexually harassed by a pupil - including one who said a sixth-form student wrote a sexually explicit story about the staff member and handed it in to them - while 7% said their abuse came from a colleague.
Some 6% said the harassment was by a manager, and 2% said it was by a parent.
Only one third of victims (33%) reported every incident of sexual harassment they experienced, compared with 42% who did not report any.
One respondent said a pupil filmed up her skirt during a lesson, while another said inappropriate, untrue and unsolicited comments from a male counterpart caused such an impact on her family life that she and her husband subsequently divorced.
As a result of the incidents, 43% of teachers surveyed said they suffered a loss of confidence, and 38% said they experienced anxiety or depression.
Almost half (48%) said they made changes to their daily routine to avoid the harasser, while nearly one third (32%) said they felt under pressure to change their appearance or style of clothing in an effort to put a stop to the trouble.
A Government spokesman said: "Teachers and school staff have a right to feel safe while doing their jobs and any form of misconduct, including harassment towards them is completely unacceptable.
"We have given schools the powers they need to tackle poor behaviour such as harassment of staff. We expect all schools to have procedures in place to support staff dealing with issues like this."