Teachers don’t understand the real meaning of the word stress, the new Ofsted head, Sir Michael Wilshaw, said today.

In a scathing attack which will raise the stakes in his increasingly confrontational relationship with the profession, Sir Michael took aim at teachers who “make excuses for poor performance,” claiming their jobs are “far too stressful”. The head of the schools watchdog was speaking for the first time in public since being attacked by headteachers’ leaders over the bank holiday weekend for “bullying tactics”.

Sir Michael told a conference of headteachers today: “Let me tell you about stress. Stress is what my father felt, who struggled to find a job in the Fifties and Sixties and who often had to work long hours in three different jobs and at weekends to support a growing family.

“Stress is, I’m sure, what many of the million-and-a-half unemployed young people today feel – unable to get a job because they’ve had a poor experience of school and lack the necessary skills and qualifications to find employment.”

He added: “Stress is what I was under when I started as a head in 1985 in the context of widespread industrial action. Teachers walking out of class at a moment’s notice, doing lunch duty on my own every day for three years because of colleagues who worked to rule, covering five classes in the sports hall when there was no one to teach them.”

Teachers were quick to fight back. Mary Bousted, general secretary of the Association of Teachers and Lecturers, said: “Please will Ofsted concentrate on helping schools to improve and stop criticising teachers and heads. It is not helpful for Sir Michael to rubbish the amount of stress teachers are under.”

Brian Lightman, general secretary of the Association of School and College Leaders, added: “Committed hard pressed school leaders who have been working tirelessly to raise standards despite a climate of public denigration, job vulnerability and spending cuts know exactly what stress is.