By Justin Parkinson BBC News Online education staff at the NAHT conference

A head teacher's lot is a stressful one, union says

A National Association of Head Teachers study found 1,500 vacancies had already been advertised this year, up 25% on the same period in 2003.

Deputy heads were also unwilling to apply, adding to potential shortages.

The union blames school budget problems, high workload and the pressures of government inspections. The government disputes its findings.

'Football managers'

Speaking ahead of the NAHT's annual conference, in Cardiff, the general secretary, David Hart, said heads were facing unrealistic expectations, similar to "football manager syndrome".

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He added: "But there the comparison ends. There are not the candidates to replace them."

Mr Hart also said: "No head will ever get a payoff of Claudio Ranieri proportions.

"The government knows it has a crisis on its hands. But it has yet to come up with an answer."

Figures from the Teacher Pensions Agency show a 270% increase in the number of teachers taking early retirement - by leaving aged 55 to 59 - between 2001-02 and 2002-03.

The NAHT found that, of the 358 primary school headships advertised in January this year, 110 (or 31%) had been re-advertised. In London, the proportion was 42%.

Governors

Mr Hart said having to deal with budget deficits meant more heads were entering the classroom, to help cover teaching shortages.

The government knows it has a crisis on its hands. But it has yet to come up with an answer Union leader David Hart

School inspections by Ofsted were adding to pressures, as were the expectations of local authorities, which had been raised by the increase in league tables and other measurements of success.

Mr Hart said: "If a face doesn't fit, the head departs. If the Ofsted inspection is not good, the person who gets fingered is the head.

"The governors often get away scot-free."

The NAHT found the job of head teacher was "increasingly high risk". The number of cases handled by the union from January to March this year was 850, an increase of 50% on the same period in 2003.

Funding worry

Mr Hart said: "The fear has to be that, unless heads are given better support by governors and local authorities, a real prospect of workload reduction, a good long-term funding settlement and rewards that reflect their responsibilities, this exodus of talent will not be staunched."

In January 2004, both head teacher and deputy head vacancy rates in maintained schools were the lowest they had been since 1997 Department for Education and Skills

The union also said that more than one school in 10 got less money this year than last, when costs exceeded budgets for many.

In a survey, a third of schools said they had not received the full 4% extra in pupil funding they were promised by the Education Secretary, Charles Clarke, when he admitted there had been mistakes in 2003.

The NAHT's poll of 806 schools in 137 English education authorities showed the distribution was uneven, as more than a quarter of them had received 8% or more extra this year.

The Department for Education and Skills said the survey was "deeply flawed and very misleading".

"Our analysis of budget statements received from 85% of LEAs so far shows no evidence whatsoever to suggest that schools are not receiving the minimum guarantee," a spokesperson said.

On head teacher posts, she said the annual census - published on Thursday - had shown that both head teacher and deputy head vacancy rates in maintained schools were the lowest they had been since 1997.