The number of teachers committing suicide in Britain each year has almost doubled, Channel 4 News learns, with educators saying they are failing to cope with the stresses of the job.
Teachers are blaming the stresses of rigorous classroom inspections, Government targets, "unmanageable" amounts of paperwork and 50-hour-plus working weeks for the increasing suicide rate and a sharp rise in serious mental health problems among school staff.
According to new figures released by the Office for National Statistics (ONS), 63 Primary and Secondary teachers took their lives in 2009 compared to 35 in 2008; a spike of 80 per cent.
Instances of suicide are now 30-40 per cent higher for teachers than the national average.
And it is older members of the profession - those in the twilight of their careers - who are increasingly representing the majority of those committing suicide: 50 to 64-year-olds account for 65 per cent of the total.
John Illingworth, former president of the National Union of Teachers (NUT) and campaigner for mental health in teachers, told Channel 4 News that the growing trend of older teachers committing suicide could be linked to another trend of younger teachers walking away from the job when they begin to find their workloads unmanageable.
I have actually contemplated suicide as a way out because the situation is making me miserable. I cannot carry on like this for much longer Teacher
"Usually people who commit suicide are already suffering a seriously depressed condition," he said.
"Increasingly, we're seeing that the school's reaction is to try and get rid of them. When that happens, teachers who have been teaching for, say, 30 years, are profoundly more depressed, like they are bereaved. These days, younger teachers may just walk away from the job when they start feeling that the stress is too much, and that is another - separate - major issue."
He added: "Although you cannot say that every teacher who commits suicide does so because of the stresses of the job, we have found that it is often one of the main aggravating factors."
In April, NUT representatives claimed that teachers were being driven to the point of suicide, alcoholism and weight disorders by the stresses of the job.
Sue McMahon, branch secretary for Calderdale, West Yorkshire, told the union's national conference: "I have seen a meteoric rise in work-related stress and in more than one occasion have had to support a member who has attempted suicide."
She added: "The target tsunami escalating from the aspirations of this Government is sweeping away those teachers that you are struggling to support. And as the wave gets bigger it is leaving a trail of devastation in its wake that used to be a world class education system."
Union leaders say that stress is now the main reason for driving teachers out of the profession, referring to figures that show 309,000 teachers - more than half of the workforce - were signed off sick for an average of two weeks in 2009.
And they often point to research commissioned by the Health and Safety Executive, which found that teaching is the most stressful profession in the UK, with 41.5 per cent of teachers reporting themselves as 'highly stressed': double the number across the working population.
Mr Illingworth said that the problem is getting worse. "Evidence shows that stress is getting progressively worse for teachers, and for a very good reason: every year, the demands of the job go up and the control they have over their jobs goes down," he said.
Teachers often cite the pressure they experience in the run-up to Ofsted inspections - the usually triennial assessment of schools and individual teachers, with grading from inadequate to outstanding. The inspections make them feel like they can "make or break their reputations, and by extension the school, so it is extremely high stakes", Mr Illingworth added.
"It's to do with teachers not trusting Ofsted, which has proved to be a very erratic inspection agency: a school can be outstanding one year and failing the next: so teachers feel there is no consistency among inspectors. They're therefore extremely nervous as they don't know what to expect, how to prepare."
Since 1998, coroners' inquests into the suicides of at least eight teachers have heard that they took their lives shortly before or after Ofsted inspections.
In 2009, 44-year-old Sarah Giddy, a teacher at St Helen's Primary School in Abbotsham, Devon, hanged herself ahead of an Ofsted inspection after complaining she was overworked and stressed.
And headmaster Jed Holmes, 53, committed suicide a day before Ofsted inspectors were due at Hampton Hargate Primary School in Peterborough. He died from carbon monoxide poisoning after lighting a charcoal barbecue in his home.
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The charity Teacher Support Network recently carried out a poll on stress and workload among teachers and showed Channel 4 News the testimonies of some school staff, who spoke of experiencing suicidal tendencies as a result of work-related stress.
One male teacher told researchers: "I was feeling totally overwhelmed by the workload and working 60+ hours a week just to hang on by my fingernails. I have actually contemplated suicide as a way out because the situation is making me miserable. I cannot carry on like this for much longer."
Another teacher, a woman, confided: "I had to have three months off work having been diagnosed with severe depression following several years of intense stress. I actually wanted to end my life."
Others complained that they had begun drinking too much in an effort to cope with the stress, taking anti-depressant drugs such as Prozac, and either eating too much or too little food because of workload.
Julian Stanley, chief executive of Teacher Support Network, said the organisation planned to carry out a comprehensive review of the teaching workforce - with the support of unions and the Department of Work and Pensions - next year.