Mike Tomlinson, who replaced Chris Woodhead as Ofsted chief, has welcomed a "really quite tremendous" improvement in the quality of teaching at primary and secondary school levels.

Only one lesson in 20 is now unsatisfactory, primary schools standards are improving and most parents are pleased with their children's education, he reported.

However, he warned that a shortage of good secondary school teachers, especially in maths, science, foreign languages, design and technology and English, could put at risk the rise in standards. The shortage meant non-specialists and temporary teachers were often being used, causing disruption for pupils.

A lack of cash, either because of poor management or the "lottery" of government funding, is also causing problems in one in four of England's secondary schools and contributing to worsening pupil behavoiur.