Come back feminism, all is forgiven? After years of slagging off the F-word, social commentators have woken up to the fact that teenage girls are adopting usernames such as “slut” and “whore” on social networking websites. They're boasting about being good at sex acts, putting themselves at risk from predatory older men and paedophiles, and one expert is suggesting - hold your breath - that feminism should be taught in schools: a “reinvigorated” feminism that is designed to appeal to young women who have never heard of The Female Eunuch but need something to counter the relentlessly sexual messages of popular culture.

Cue cries of outrage from assorted misogynists, but Dr Jessica Ringrose has a point. I would say that, of course, being one of those Seventies radicals who has never, ever, felt ashamed of calling herself a feminist. But the research of Dr Ringrose - who works at the Institute of Education in London and whose conclusions have just appeared in the Times Educational Supplement - could hardly be more timely, coming at a moment when there is growing anxiety about the sexualisation of girls and women. Schoolgirls, she says, increasingly link their personal worth to being sexually attractive. She is calling for young women to be offered alternative role models to the ubiquitous celebrities - such as Britney Spears, Paris Hilton and Christina Aguilera - who embody the must-have look for young women in the 21st century.

So far, so good, and I wouldn't quarrel with Dr Ringrose's assertion that teenage girls are being encouraged to define themselves through their bodies - by, in her words, “being thin, having fake boobs”. For women of my generation, the misogynist message of this body shape could hardly be more obvious, but few teenage girls stop to ask why they are being encouraged to look like boys with breasts.

I'm not sure, though, that the alternative role models Dr Ringrose suggests will mean much to the girls who have grown up with MTV and YouTube. Much as I admire Emmeline Pankhurst and Virginia Woolf, I assume I'll have to explain who they are if I mention them to my goddaughters. Pankhurst, Woolf, Marie Stopes and other feminists active in the first half of the 20th century belong to a different world, even if they would recognise some contemporary concerns - for instance, the scandalous fact, reinforced this week in a study by the Office of National Statistics, that women still have not achieved equal pay.

Where have all the real men gone?

Top American columnist Kathleen Parker argues that feminism has neutered men and deprived them of their noble, protective role in society

• Hurray, we’re being heard at last

BACKGROUND

• Working women no longer want to be men

• The rise of Dolly Parton feminism

• Legacy

• How did Seventies feminists fare?

• Are men really necessary? Good question

That was a big issue in the Seventies, but far from the only one. We didn't want to be like our mothers and grandmothers, and I can't remember a moment when I wasn't a feminist. By the time I was 14 I scorned anyone who told me that girls couldn't do something. I argued for the right not to have children, which seemed to shock people no end. Looking back, I'm amazed at how much we achieved - many feminist ideas, such as the right to maternity leave, have become mainstream - but I'm also horrified by the casual misogyny of 21st-century life. Since my book, Misogynies, was first published in 1989, it has got much worse.

But 21st-century politicians don't use the vocabulary of their 20th-century forebears, and feminism needs to reinvent itself as much as any other political movement. It needs to address teenage girls in a modern language that doesn't reinforce the worst stereotypes about feminism; I still come across diatribes which suggest that all Seventies feminists were man-haters who wore dungarees. Using a radical fringe to discredit an entire movement is the oldest trick in the book, but you can't expect 16-year-olds to recognise it, any more than you can expect them to have read The Hite Report on Female Sexuality - by one of feminism's most beautiful and stylish activists.

Indeed, I worry that there has been a generational slip - that a generation of teenage girls has missed out on feminist ideas and is having to deal with an increasingly exploitative culture without the tools to look beyond the surface glitter. Few of them realise, when they jokingly call themselves “sluts” and “whores”, that they are using male words that have always reflected contempt for women. It may be cool to talk about “hos” and “bitches”, using a vocabulary lifted from rap music, but I'm not surprised to discover from Dr Ringrose's research that teenage girls still fret about being seen as “slutty” if they go “too far” sexually.

That's the trouble with this kind of faux-liberation. I've seen it all before, as have most women of my generation. But it's no good talking to teenage girls about objectification and patriarchy when they have grown up with the casual vocabulary of teen magazines and the internet. In fact, I'd go farther than Dr Ringrose and argue that it's no good teaching feminism only to girls when their male contemporaries are just as vulnerable to the ghastly messages of lads' culture.

We need feminism more than ever, not just to address all the myths that have grown up - we're still a long way from living in an equal society, despite girls' much-vaunted success over boys in exams - but to counter the pervasive influence of the commercial sex industry on young women. The stage costumes of female stars, from Kylie Minogue to Aguilera and Spears are an obvious example.

Schoolgirls who choose usernames like “freesex” in chatrooms need to realise that they have been conned into thinking that such behaviour is harmless. They have also been bombarded with messages that pole-dancing is good, clean fun, encouraged by female celebrities who show off about visiting clubs with their boyfriends. I mean, why not pay your way through college by pole-dancing in the evenings? No one tells teenage girls about the rise in sex crimes in neighbourhoods where pole-dancing clubs operate, or the pressures on young women who work in them to have sex with customers.

Teenage girls can find out about the suffragettes for themselves, if they are interested, but a new version of feminism should offer a lot more than history lessons. It has rarely used the language of human rights, but that's what feminism is really about, and it's by linking it with those ideas that feminism can be made modern and up-to-date. One of my goddaughters recently became the secretary of the Amnesty International branch at her university, and teenagers and young adults are used to seeing pictures on TV and the internet of orange-robed monks defying Chinese troops.

Sex - currently one of the biggest illegal businesses in the world - is just as much a human rights issue, a fact that becomes apparent as soon as someone explains to teenagers that girls as young as 14 are being lured to work in bars and restaurants in the UK, only to find themselves locked up in flats and forced to have sex with hundreds of men.

If sex-traffickers habitually abuse women as “whores” and “sluts”, what does that say about teenagers who use the same language on social networking sites? Do they really want to behave like men who so obviously despise women? What do they think about boys just a bit older than themselves who pay for sex with prostitutes? There needs to be a moral code which would allow teenagers to explore sex on terms which aren't degrading to themselves and their friends.

Women's studies has gone out of fashion as a subject at universities, so let's start dealing with these questions in schools, as Dr Ringrose suggests. Young women need to know that there's nothing wrong with liking clothes, shoes and boys (or other girls), but they're also in urgent need of a language and ethics that allow them to be themselves. That's what feminism did for me, and I long to see the next generation of young women freed from incessant demands to turn themselves into the self-hating Barbie Dolls of the commercial sex industry.

Explore Women

• Fashion

• Beauty

• Diet & Fitness

• Relationships

• Families

• Celebrity

• The Way We Live

• Horoscopes

Times recommends

• How I lost the gift of joy for a while
• How to get Coleen Rooney's post-baby body
• The A-Z of winter style rules