Thousands of pupils identified as having special educational needs are wrongly diagnosed and simply require better teaching, according to a new report.

Ofsted said that as many as half of all pupils labelled as having the lowest category of special needs, School Action, would not be identified as such if schools focused more on teaching for all their children. Inspectors visited 228 nurseries, schools and colleges in 22 local authorities, and carried out detailed case studies of 345 young people.

Ofsted's chief inspector, Christine Gilbert, said: "Although we saw some excellent support for children with special educational needs, and a huge investment of resources, overall there needs to be a shift in direction."

But Christine Blower, general secretary of the National Union of Teachers, said that such claims were "insulting and wrong".

"Teachers do a great job in often very difficult circumstances to meet the needs of all their pupils, and for Ofsted to suggest otherwise is both insulting and wrong."

She added that all too often schools were "left without the necessary backup and support that is required" to meet pupils' needs.

Currently 1.7 million school-age children, or just over one in five pupils in England are identified as having special educational needs.