15/09/2015 11:25 BST | Updated 15/09/2015 11:59 BST

Private Boys Schools Produce 'Sexist Lads', Says Leading Head Mistress

"Private boys’ schools produce ‘sexist lads'," according to Clarissa Farr, head mistress of the renowned St Paul's Girls School in London.

Farr made the comments after realising some of her former pupils began leaving highly reputable companies in the UK during the early stages of their careers.

“The sexism is driving the girls out,” Farr told The Sunday Times.

“They do not want to stay. Several young women have spoken about being mocked or frowned on by their managers because they have drawn attention to a laddish culture — of which the central ingredients are sexist attitudes, drink and football — which prevails among young male employees and which excludes them. It’s a low-level discrimination which undermines women."

Clarissa Farr, headteacher of St Paul's girls school

She continued: “Girls educated in girls’ schools have no experience of this kind of thing, as they are used to being taken seriously and will therefore find it quite shocking."

Farr’s school charges up to £22,500 a year and entry is gained through competitive examination and interview. The school says it encourages high standards of achievement which is echoed through the school's examination results. In the summer of 2015, 57% of A-levels taken at St Paul’s Girls’ School were graded A*, as were 94 per cent of GCSEs, and 99% of GCSEs were A* or A. Alumni include the actress Rachel Weisz, the former acting Labour leader Harriet Harman and the writer Rachel Johnson.

The head teacher called on private boys’ schools to give their sixth-formers lessons on how to take women seriously at work instead of indulging in banter about drinking, football and sex. “It would be wonderful to see boys’ schools making a point of addressing issues of equality so that young men are equipped to work alongside young women of comparable ability without difficulty," she said.

She might be doing her job in the classroom, but Farr also believes it is the role of employers to push for equality. “Firms need to build a reputation for taking women seriously and giving them equal opportunities to be ahead of the pack.

That would speak very powerfully to girls who experience that and are not finding it," she added.

The headmistress' opinion echoes those of the nation's MEPs who approved a non-legislative resolution which would call for the end of gender stereotypes and would close the gap between women's education and professional development in order to increase female representation as a whole.

The recently released 'Empowering Girls Through Education' report suggested that schools should be guided ‘to embrace a gender perspective and gender equality, and to ensure the elimination of stereotypes and sexist distortions that textbooks and teaching materials may include in their content'.

Farr has previously warned of “snowplough” parents who are so over-protective of their offspring that the children end up unable to deal with failure.