I recently came across a 15-year-old pupil of mine absolutely beside herself with grief. After a certain amount of cajoling, she eventually wailed that some boys in her class had called her “brainy”, before bursting into a fresh flood of hysteria.

Fumbling for the Kleenex, and wondering - not for the first time - what the hell had happened with feminism and this generation of teenagers, I attempted to mop up her tears and explain that being described as “brainy” was a Good Thing and something she should be pleased about, even if the idiotic boys were too stupid to recognise that. “I love being called brainy,” I said, soothingly.

These words had the desired effect, or so I thought. She instantly stopped crying and looked at me in astonishment. “But that’s nasty, Miss,” she cried.

It was now my turn to look puzzled. She sighed. “Miss, being brainy means you give head to a lot of people. Giving brain means giving head.”

This conversation crystallised something that had been nagging at me for quite some time.

Language is a powerful signifier for all humans, but perhaps more for teenagers than most. For them, language is not just a tool of communication, but a means of establishing class, race, religion, which part of town they’re from, the music they listen to, the groups to which they are affiliated and myriad other things that adults forgot when they hit 20. This has always been the case, but what is new among the teenagers I work with is the casual appropriation of what were once compliments as insults - invariably targeted at females. If a girl “gives character”, she needs slapping down. If she’s “lively”, she’s slutty.

Teenagers are not particularly thoughtful about their words or actions, so when you spot a trend, worrying or otherwise, the only way to understand it is to ask them why they’re doing it. It is actually surprising how much this question surprises them - but it gets them talking.

“Sex is a way to get girls to do more stuff weirdly. If they do something and you threaten to tell everyone, they do more stuff.”

“I hated giving blow jobs, but didn’t want to look weird. And he said I was a freak if I didn’t. He was my best mate, but sex turned him into someone else.”

If this was a purely linguistic trend we could all sigh with relief, put the kettle on and hope it goes away. But it’s not just a linguistic one. It is manifesting in the thoughts, actions, character and behaviour of teenagers everywhere, and if you think it’s just the bad ones, the naughty ones, the poor ones, the sink estate ones, you are being very naive indeed.

This is, thanks to the internet, the first generation with free, easy and mass exposure to hardcore pornography. These are the first teenagers to have grown up with “sexting”, sex tapes, making their own sex tapes on phones, saucy snaps of classmates on Facebook, MSN orgies and extensive insight into the sex lives of celebrities and politicians - hell, even teachers.

It is impossible to discuss the long-term effect this will have on a generation of teenagers because we’re not there yet, but I can tell you about the short-term effects. I’ve been observing them closely for a couple of years. And some of what I’ve witnessed would be shocking to less seasoned adults.

Take, for example, James Deen - the new big breakout crush in the US who’s also gaining fans over here. I’ve spoken to dozens of girls over the past couple of months who have admitted to watching his films and finding him “hot”. Deen is an unusually pretty-boy porn star. Somewhat belying his rather sweet looks, Deen mostly appears in ultra hardcore films that go under the genres of Everything Butt (extreme anal sex), Bound Gangbangs (gang rape) and Public Disgrace (the previous two combined, but also including women being smacked about).

I don’t necessarily judge the fact that girls (and boys) are watching these films, but I do worry about their responses to them and what it says about the way they view sex, and themselves. Girls’ first crushes were once anodyne, harmless guys (Donny Osmond, New Kids on the Block, Take That) who provided a shark-free way for them to dip their toe into the water of their burgeoning sexuality. While girls still crush on the likes of Justin Bieber and Robert Pattinson, the widening fascination with Deen is telling - and worrying.

Boys emulate the men the girls have crushes on. And if they see (and they will) this porny dreamboat smacking women about, fucking a woman up the arse while someone else does her vagina and simulating rape - and observe that so many girls fantasise about Deen - what sort of message does that send to a teenage boy? Calling women “bitches” will suddenly seem positively polite. To make matters worse, Deen is about to appear in a mainstream film with Lindsay Lohan, so Deen-mania is certain to intensify.

Warped expectations

The hardest conversation I’ve ever had was with a distraught, confused man of about 45. I had to explain to him that we had to exclude from school his seemingly non-abused, non-disturbed, well-loved daughter because she had been caught administering fellatio to a line of young men in the boys’ toilets for cash.

And it wasn’t altogether unusual: there are many schools that have (but don’t advertise) policies and methods for dealing with sex acts taking place on the premises. A friend of mine who teaches at another school (much more posh than mine) said that it had got so bad they had to go on “blow-job patrol” every lunchtime.

When you ask why, the overwhelming conclusion is that, just as teenagers will wear the fashions and drink the drinks they are bombarded with images of, or try the substances their favourite celebrity is dabbling in, they are going to copy the porn images they see several times a day. Parental control locks on family computers are pointless: the kids have smartphones.

The effect that mass exposure to pornography is having on teens’ emotional well-being and self-esteem will take time to gauge properly as it is an unprecedented phenomenon happening in real time. However, the impact it is having on the way they view their bodies and the bodies of the opposite sex is already very evident.

After a recent (completely unrelated) classroom debate on the right to express views on religion without people taking offence, I showed some Year 11 students Monty Python’s Life of Brian. In the scene where Judith leaps out of bed naked to protect the reluctant messiah from his nosy mother, full 1970s bush proudly on display, one of the male students turned to me, eyes wide, and without a trace of knowingness asked: “Miss, is she wearing a merkin on her fanny?”

It was a hilarious question that made me laugh for a week, but it exemplified just how distorted the female form has become in the minds of teenage boys - owing, I believe, to pornography. I think it’s fair to say that Year 11 boys don’t see many “fannies” in real life.

This was consolidated by a discussion a little while later in sex education where most of the boys stated that pubic hair on women was “disgusting” and “should be shaved off” and this of course led me to ask why. After much sniggering, they answered that women in porn don’t have pubic hair. (When I asked them if their penises all looked like the ones on the men in porn films, there was of course a deathly silence.)

So where does this leave the girls - the teenage girls who are represented in pornography as the holy grail, the ultimate fantasy? Nowhere good, that much is certain. There was a time when the biggest body issue for teenage girls was thinness, and the biggest worry was that they might develop eating disorders.

Now, however, this body dysmorphia has extended to plastic surgery and body alteration. I have lost count of the teenage girls who have told me about their desire to have their breasts surgically enlarged. While this is undoubtedly due in part to many female celebrities being cosmetically enhanced, it is also because boys vocally favour the two-doormen-in-a- headlock look over something more natural. And where are boys developing this preference? Porn, of course.

If boys’ pornography-prescribed aesthetic desires are influencing how girls see themselves and what they do with their bodies, what the hell is going to happen to the actual sex lives of teenagers? Boys and girls brought up on a diet of extreme and hardcore pornography are going to have a pretty distorted attitude to their own sexual boundaries, the pressure ever on to keep up with the stuff they see on the internet.

Schools are having to deal with the new phenomenon of pornographic bullying on phones and social media. All too often, I hear of some inappropriately smutty or downright shocking pornographic picture or film of a schoolchild being passed around among students. Girls tell me they suffer enormous pressure from boyfriendsfriendspeers to “sext” (send a half or fully nude picture of themselves andor a sexually explicit explanation of what they are going to do later).

Replicating what they see

When the press expresses concern over the sexualisation of teenagers and shrieks “How and why is this happening?”, the curtain-bitingly obvious answer is that teenagers have not suddenly become wannabe porn stars. They are replicating the attitudes and behaviours of something they see on a daily basis.

As little as 10 years ago, experimenting with sex was considered to be something you gave a great deal of thought to. Pornography has made sex seem more casual, creating a generation of teenagers who are not only au fait with, but have in a way reclaimed as their own, the notion of friends with benefits, no strings attached, sexting, slutting, fishing and a million other acronyms and slang terms I’ll never understand now I’m not a teenager.

This is a generation that has grown up able to access gang bangs, rape, the coprophagic video Two Girls One Cup, the Paris Hilton sex tape 1 Night in Paris, Kim Kardashian, girls who like to be beaten and most of all teens: horny teens, teens get ass-fucked, teen loses virginity, teen gets fucked by older man, teen gets raped, all ad infinitum at the touch of a button.

I am not in the least surprised that girls are going starry-eyed over Deen. He’s doing what they see all the time, but he’s handsome and probably does what he does well. My job as a teacher is not to judge. It is to see and, I hope, sometimes to impart. So I’ve seen this - and there isn’t enough space to tell you all I have seen on this front. I am not a parent, but I do often speak to terrified parents about such things and if a parent was to read this and ask “What can I do about it?”, I’d impart the following.

You cannot stop your teenager looking at and getting off on porn. And so you have to be brave enough to have an honest dialogue with your kids. Explain to your sons why slapping women during sex, or calling them bitches or expecting them to give “brain” is not cool. Explain to your daughters why sending sexy snaps on their phones is a bad idea and just plain wrong. Consider this conversation the Green Cross Code of their minds and bodies. Because if you don’t, you leave their sexuality, sexual well-being and sexual identity in the hands of the sex industry. It would be nice if we got back to a place where boys describe girls as brainy, lively and full of character in the real sense.

I want teenagers to snog and grope and play safely, lovingly and willingly. Because that’s what teenagers should be doing. But the fact of the matter is that adults created pornography and it has become an attractive aspiration for teenagers. And we cannot blame them or judge them for their reaction to this extremely questionable legacy. We can only help them to manage it as best they can.

What next?

Lay out the ground rules for the classroom before introducing sex and relationships education.

bit.lyGroundRules

Address the issue of pornography with the help of this guide from SexEdUKation.

bit.lySexEdUKation

Use this presentation to teach your students about the moral and legal implications of “sexting”.

bit.lysextingPPT

A Teachers TV video focusing on the pressure to have sex is useful for key stage 3-4 PSHE lessons.

bit.lyTeachersTVpressure

This thought-provoking worksheet gets pupils to consider who is affected by underage sex.

bit.lyunderagesexworksheet

Live webchat

The author of this article, Chloe Combi, and PSHE expert Alice Hoyle, who is also a teacher, will be taking part in a live webchat on Wednesday 17 October at 6pm on the TES website.

The pair will discuss this article’s conclusions about the impact of widespread access to pornography among today’s pupils and how schools and teachers can or should manage the consequences. They will answer your questions as submitted by email or on Twitter.

For more information, please visit www.tes.co.ukwebchats.