Many secondary schools are still having trouble recruiting and keeping teachers - but vacancies have dropped by almost a quarter in the past year, an unofficial survey suggests.

The research, by the Times Educational Supplement and the Secondary Heads Association, claimed many head teachers were taking on staff they would not normally consider for employment.

On the basis of their poll of 715 state and 97 private secondaries, they estimate that staff vacancies across England and Wales stood at 3,769.

Heads want to provide good quality teachers

This was well down on the 4,926 vacancies estimated in a similar poll last year, but still well above the government's figure of 2,450, from the January census.

Heads surveyed said a fifth of the appointments they had made this year were "unsatisfactory", typically because of the number of teachers taking lessons in subjects for which they were not qualified.

Schools in eastern England, the West Midlands and London reported the highest number of unsatisfactory appointments, while the capital had the biggest portion of the unfilled vacancies.

'Non-specialist' teaching

In total, an estimated 3,261 teachers were taking classes in English, maths, sciences or languages when they were not specialists in those fields.

Secondary heads have been forced to make many appointments with which they are not happy

John Dunford, Secondary Heads Association

Teacher shortages were also making an impact on the independent school sector, with many top schools such as Cheltenham Ladies' College and Roedean finding they had fewer applicants for posts.

Richard Moore, the head of Fakenham High School in Norfolk - a beacon school with specialist status - has had to appoint 24 teachers including part-timers for the coming school year.

"We had seven newly qualified teachers starting last year and have only been able to retain two of these," he said.

Cost of recruitment

"Five have moved on to more attractive jobs or left the profession. It's alarming people coming into teaching are leaving so soon.

"The majority of our teaching staff are coming up to retirement age in five or seven years' time. I don't see the numbers coming in to replace all of these."

He added: "If you are spending �20,000 to �30,000 a year on advertising that's money that could be better spent on text books or another teacher for a year."

The general secretary of the heads' association, John Dunford, said: "For the second year in succession the survey has revealed that secondary heads have been forced to make many appointments with which they are not happy.

"Only by doing this have heads been able to keep down the number of vacant posts.

"They have had to use all their ingenuity to fill many posts this year, including visits abroad and interviews over the phone."

'Inaccurate figures'

The Department for Education said the TES/Sha survey had been carried out for the past three years and its figures were "inaccurate".

"For instance in September 2000 they said that there were over 4,000 vacancies in secondary schools when the actual figure was 2,645," a spokesperson said.

"They were out in September 2001 when they forecasted almost 5,000 when we know it was half that.

"Experience shows it is better to wait for the real figures. We are not complacent for one moment but we are making real progress."

There were over 20,000 more teachers in place than in 1997, the spokesman added.