Millions of children are being subjected to 'dull and uninspiring' lessons that hold back achievement and fuel classroom indiscipline, Ofsted warned yesterday.
The schools watchdog said teaching in half of secondary schools was sub-standard and called for incompetent teachers to be removed.
On the eve of an education white paper proposing a shift in teacher training, Ofsted's chief inspector, Christine Gilbert, said low expectation of pupils and teachers' poor grasp of their subjects, have let down children.
In the worst lessons, teachers had patchy subject knowledge, failed to ensure children understood key concepts and allowed the marginalisation of traditional subjects including history and geography.
Inspectors who visited 845 secondary schools in 2009/10 found that teaching was merely 'satisfactory' in 45 per cent and 'inadequate' in five per cent.
At primary level, teaching was satisfactory in 39 per cent of 4,620 schools checked and poor in five per cent.
Christine Gilbert called on schools to take a tougher line against 'really poor and struggling' teachers. They should be eased out of their jobs, she suggested.
Delivering her annual report, Miss Gilbert, who is expected to step down next year, said: 'The fact is that there continues to be too much teaching that is dull and uninspiring and this makes it harder for pupils to learn.
'This means that too many young people are not equipped well enough to make the best of their lives.
'Teaching is also a big factor in poor behaviour as well as uneven exam results. The problem is not just one for the weakest schools. Too many schools tolerate pockets of poor teaching alongside good practice.'
'I certainly think if a teacher is really poor and struggling, she or he is not getting satisfaction from that job and there should be a dialogue about the other opportunities that person might want to have. But I would always go for professional development first.'
Christine Blower, general secretary of the National Union of Teachers, said: 'Our classroom teachers do an amazing job day in, day out, in often challenging circumstances.
'As Ofsted says itself, when you look beyond the sensationalist spin on the quality of teaching on our schools, "inadequate teaching" is the exception rather than the rule.'
Figures published earlier this month suggest that poorly-performing teachers are simply being moved around the system. Head teachers say they often face union pressure and red tape when attempting to fire failed staff.
In 72 local authorities – almost half the total – not a single teacher has been fired for incompetence in the past five years, while dozens of poorly-performing teachers have been handed 'golden goodbyes' totalling £2.3million.
Education Secretary Michael Gove's White Paper, 'The Importance of Teaching', is expected to include a series of reforms aimed at raising the calibre of the teaching force, including tougher entry standards, greater monitoring of performance and flexibility for schools to pay good teachers higher salaries.
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