Female teachers are financially better off in state schools

The hourly rate for female private school staff is 7% lower for maths, science and engineering.

In other subjects, women earn 13% less, according to the Economics of Private Schools study, completed by academics.

Men, however, earn up to 22% more in independent schools, illustrating the gender pay disparity.

The research compared male and female secondary school teachers with similar levels of experience in the two sectors over a 10-year period from 1996 to 2006.

From 2001 to 2005, it found the average weekly pay for women in state schools was �517 but just �503 in the private sector.

Women in private schools do pay a modest penalty Professor Francis Green, co-author, study

The average weekly salary for men was �635 in the state sector and �704 in private schools during the same period.

The survey, carried out by Professor Francis Green of Kent University and Professor Stephen Machin of University College London looked at data from the government and the corresponding figures from the Independent Schools Council (ISC).

Professor Green told the BBC News Website: "Women in private schools do pay a modest penalty.

"We don't have an explanation for it, but it could be that they get benefits which aren't necessarily mentioned in pay, for example, if they have children and want them to have a private education, they might get reduced fees."

State 'shortcomings'

The advantages of working in private schools include longer holidays and a better working environment, say some women teachers - and they find salaries are better too.

Helen Whittaker, who jumped ship from state to private sector, believes she is better off all round.

The 30-year-old chemistry teacher who works at Wolverhampton Grammar School, said: "I took a pay rise when I left the state sector.

"I started my teaching career in Reading then moved back to Wolverhampton to take a job in a local comprehensive.

"I found there was a lack of prospects and nothing to aspire to at the comprehensive.

"There was no incentive. A lot of the kids weren't interested and it turned into a bit of a battle to teach them.

"Wolverhampton Grammar School is a nice place to be. Staff morale is very good, it's a nice working environment and the children want to learn."

The grammar school job was a sideways move for Ms Whittaker but she found herself �5,000 a year better off, with the added bonus of three weeks extra holiday, compared to her state colleagues.

Reinforcing Ms Whittaker's comments, an ISC spokeswoman said: "The research itself concludes that 'independent school teachers work with fewer pupils and enjoy longer holidays and, in the case of women, shorter weekly hours'."