"Some boys or girls, they expect that sex is violent — [that] it is OK to use chains or whips, to hurt someone."

These are the words of a teenage girl, and similar statements are leading experts to warn that internet pornography is fast becoming the primary way young people learn about, and understand, sex.

Thanks to modern technology, pornography has become more accessible and more normal than ever, and sex educator Maree Crabbe says it is a pervasive problem.

"Porn is arguably the most prominent sexual educator for many, perhaps all young people," she told 730.

"They're seeing a normalisation of sex acts that most people in the real world aren't engaging in or are not keen on."

Psychologist Russell Pratt said many young men believe the fantasy they see on the screen is real, and that the common porn script often includes violence or aggression towards women.

"If a young person who is 13 or 14 years old has been looking at porn for maybe a year, most likely hasn't had any sexual activities or sexual interaction with anyone, really why wouldn't they believe it?" he said.

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"It doesn't look gentle, it doesn't look particularly loving and it doesn't look like much fun.

"It looks painful, it looks brutal."

School student Annie Hill said hardcore sex was becoming the norm. ( ABC News )

Eighteen-year-old Annie Hill said she had seen how pornography affected the behaviour and expectations of boys.

"Hardcore sex like that is the norm," she said.

"All the available porn is like next-level stuff; it's like there's no romance affiliated with sex anymore."

She said there was increasing pressure on young women to comply with boys' demands.

"The boys want to be dominant," she said.

"They think your body is something they can share around, do whatever they want with it.

"There's no romance affiliated with sex anymore."

'It becomes the foundation of what they think a relationship is'

Author and women's advocate Melinda Tankard-Reist said she could not keep up with the requests from schools to go and address students on the topic.

She said girls were struggling with terrible pressures and image problems in a highly-sexualised environment.

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"I go to schools where 12- and 13-year-olds will show me on their mobile phones the number of requests they've had that day for sexual images [from] boys," Ms Tankard-Reist said.

"They cannot develop healthy respectful relationships when pornography is their formative environment.

"They are looking at porn as a sex education handbook, which can only have damaging impacts."

The ABC spoke to students at Heathdale Christian College in Melbourne after an address by Ms Tankard-Reist.

They confirmed that in their world, pornography was pervasive.

"For a lot of people it becomes the foundation of what they think a relationship is," one student said.

"People are pressured so much these days that they feel like they don't have any choice, and that is what is really bad."

"It puts a lot of pressure on us girls, of how we have to act sexually to please boys," another said.

Ms Crabbe said she believed it was vital that pornography was discussed in all schools.

"Teaching about porn has to be part of contemporary sexuality and relationships education and if it's not, we're kidding ourselves," she said.

"We need to inspire young people that sex in relationships can be better, a lot better, than what they see in porn."