Teenage girls are being "manipulated and confused" by would-be celebrity role models like pop star Miley Cyrus, a leading head teacher has warned.
Stars who start out as clean-cut TV characters and then reinvent themselves as controversial and raunchy performers are sending mixed messages to schoolgirls, according to Jo Heywood of Heathfield School in Ascot.
She singled out Cyrus, who began her career playing Disney's Hannah Montana, but has recently attracted criticism for a series of provocative performances including one at MTV's Video Music Awards in the United States last month.
Writing on the Independent School Parent website, Mrs Heywood said she had hoped that after last year's London Olympics, girls would have a new generation of women to look up to.
"For a moment back in 2012, there was talk that today's generation of young women had some worthy female role models," she said.
The achievements of Olympians such as Jessica Ennis, Nicola Adams, Katherine Grainger and Victoria Pendleton made it seem that " finally women were being recognised for their achievements rather than their looks, which reality show they were on or which celebrity they were dating".
" As head of an all-girls school, I have long been yearning for more appropriate female role models for today's young women to look up to. We knew what these sportswomen stood for - hard work, sacrifice and achievement. They were clear-cut role models for young women to look up to and they did so," Mrs Heywood said.
"Now, a year on, I am not so sure that anything has really changed. I am more than a little concerned that some of the so-called role models young girls may look up to are giving them confusing mixed messages."
She added: " Fast forward to the end of the summer and another example of how young women are being manipulated and confused by potential role models. Many young girls have probably grown up as fans of Disney's Hannah Montana. Hannah, played by petite and pretty Miley Cyrus, was the archetypal all-American teenager: a girl to look up to and for parents to probably not be too concerned about.
"A few years later and we find Cyrus giving a headline-grabbing and controversial performance at the MTV Video Music Awards. Worryingly, Miley has apparently said she does not know what all the fuss is about. However, I think there is plenty to be concerned about, especially when these once clean-cut role models steer another course so publicly."
Mrs Heywood said her school - a private girls boarding school for 11 to 18-year-olds - was taking a close look at the "confusing" way women are represented in the media.
"Equipping teenagers to make sense of what the mass media presents in their formative years is something which I believe is key to developing their own sense of self-esteem, now more than ever."
Following her VMA appearance last month, Cyrus has appeared unconcerned by the controversy, later saying she had paid no attention to negative reactions.
The star has also been involved in a public spat with Sinead O'Connor after the Irish singer warned Cyrus not to be exploited by the music business.
During an escalating war of words Cyrus hit back and invited O'Connor to a face-to-face chat to air their differences.
The offer came after the Irish singer said she was ''extremely concerned'' about the US singer's Wrecking Ball music video, in an open letter on her website.
Cyrus, 20, responded by mocking the Nothing Compares 2 U singer in a series of Twitter posts . She also reminded her followers of O'Connor's past by posting a picture of her tearing up a photo of the then pope, as well as a screenshot of the Irish singer's tweets from last year in which she referred to her mental health issues. O'Connor responded demanding an apology.
Mary Bousted, general secretary of the Association of Teachers and Lecturers (ATL), said: "With the greatest ever proportion of women gaining degrees, and with girls outperforming boys in school at many levels, it's disgraceful and damaging that the majority of women young girls see pictured in magazines are airbrushed celebrities.
"This constant bombardment of images in the media demonises those who do not conform to the unrealistic and narrow depictions of the female body.
"ATL members report that body image pressure not only impacts on female pupils but increasingly leads to low self-esteem, lack of confidence and anxiety in male pupils too.
"With academic and other social pressures young people already have enough to deal with. Comparing and competing not only with their peers on looks, but with airbrushed celebrities in the media, only leads to misery.
"Children and young people need role models who enable them to see themselves reflected positively in society, across race, ethnicity or body type."