Researchers for the National Union of Teachers found that workload created the most stress. More than three-quarters complained of problems such as an overcrowded timetable, lack of non-contact time, too much marking and too many meetings.

One teacher with 25 years’ experience summed up the mood: “Stop telling me how to do my job.”

The findings - which follow a similar NUT survey in primaries published last November - come as general secretary Doug McAvoy announced he was pressing the Government for a new national contract.

It would guarantee preparation and support time for all teacers; include statutory class-size limits from early years to sixth-form; and agree that all new duties placed on schools would be costed and paid for.

The survey of 150 NUT secondary members, found that almost half were concerned about exams, coursework and assessment, while a quarter were trying to cope with changes such as the new national curriculum, or preparing for school inspection.

Four out of five said teaching itself was the part of the job they enjoyed most, while 43 per cent enjoyed the teamwork.

One teacher wrote that her daughter had gone through the list of hobbies of all the adults she knew. “When she said: ‘Mummy’s hobby is marking,’ it made me feel something isn’t right,” she said.

NUT conference, 4-5