Image copyright Getty Images/BBC

You might remember a condom on a banana, or just a general sense that if you have sex, you'll either get A) pregnant or B) a disease. We're talking about sex education at school.

The messy corners of growing-up were tiptoed around by teachers who couldn't even bring themselves to say "penis".

So when the TV show Sex Education - which centres around two students who set up a sex clinic in their school - first debuted on Netflix last year, it was a breath of fresh air.

The first series boldly tackled topics including slut-shaming, abortion, virginity and masturbation - which Aimee Lou Wood, who plays Aimee Gibbs, told Radio 1 Newsbeat she "thought was only a boy thing".

Image copyright Getty Images Image caption Aimee has one of season two's most-talked about storylines

Growing up, Aimee thought she was a "weirdo" for wanting to masturbate.

And when filming the series the 24-year-old found that other people felt the same.

"When I filmed a masturbation scene, extras were asking me, 'What do you mean you had a scene like that? That's only for boys'."

Chatting to some of the show's cast at the season two premiere it became obvious that lots of them feel they didn't learn enough about the realities of sex growing up.

"Food, jobs, sex... it's a very key part of life and we don't know enough about it," Aimee said.

"I wish I knew it was normal to want sex for pleasure, and not just to make babies."

The character Aimee plays has one of the most talked about storylines of the series. She is sexually assaulted and the series sees her coming to terms with what happened.

The storyline received huge reaction online.

Aimee says her storyline had a "huge impact" on her.

"I had to go back to when I was that age and how trusting I was. A lot of girls will relate to it."

'Everyone can learn something'

Image copyright Getty Images Image caption Emma Mackey's character deals with her mum's addiction issues in the second series

Emma Mackey, who plays the show's female lead Maeve, agrees that the programme is important in challenging taboos.

"The show makes you feel less lonely; I wish it existed when I was at school to make me feel more normal," she told us.

When asked what they'd learnt during filming, the word "vaginismus" was quick to leave almost all cast members' mouths.

The NHS says: "Vaginismus is when the vagina suddenly tightens up just as you try to insert something into it."

Tanya Reynolds, whose character Lily has vaginismus, said: "I didn't even know it had a name. So many women will watch this and realised there's not something wrong with them."

What are schools teaching about sex?

As of spring 2020, it will be compulsory for all primary schools in England to teach "relationships education", which looks at friendship and emotions. Sex education in primary schools is not compulsory.

English secondary schools must teach relationship and sex education (RSE) lessons.

Parents can specifically request for their children not to be involved in sex education lessons, but not relationship lessons.

The government's new requirements for secondary sex education include STIs, pregnancy, contraception and miscarriages.

Scotland announced plans to review RSE lessons last year, to include things like sexual harassment and consent.

Wales will be introducing a new compulsory RSE curriculum in 2022.

Northern Irish schools must teach RSE lessons, but individual schools can decide the content.

Image copyright Getty Images Image caption Patricia says the series taught her a lot "on and off screen"

The programme has been commended for showing sex in a more realistic way than most.

It replaces your average lowly-lit romantic sex scenes with clumsy, awkward ones where the teenage characters mostly have no idea what they're doing. This meant the cast had to be comfortable during the filming process.

Patricia Allison, who plays Otis's new girlfriend Ola, said: "There was a sex director on set. They sent us a list before we had even read the script to ask how we felt about certain things.

"Even if you said you were OK with something, you can change your mind and say I'm not comfortable with it today. And that's OK."

She says filming the series taught her the "importance of saying no".

'Setting the bar high'

The first season of Sex Education was one of two programmes that Netflix released viewing figures for.

It was reportedly watched by more than 40 million households in its initial weeks. (That's people who watched 70% or more of an episode).

The series has been highly praised for its diversity and representation in its casting and plot, which Emma says "shouldn't be a big deal".

"We're setting the bar high in that regard, but it's about time. It should be normal."

Otis' sexually-liberated best friend, Eric, struggles with homophobia and the relationship between sexuality and religion.

Ncuti Gatwa, who plays Eric, said: "I love that this gay, black kid is not apologising for being who he is."

The teaching of "LGBT content" in schools hasn't always been accepted.

Last year there were ongoing protests outside a primary school in Birmingham which taught pupils about same-sex relationships as part of a teaching scheme called No Outsiders.

Some parents said it contradicted their Islamic faith and was not "age appropriate".

The school compromised, with a new equality programme after consulting with parents. The government says it encourages secondary schools to include LGBT issues in sex education.

Ncuti said: "Representation matters, to educate kids about all the different types of people in the world so that when they encounter them they're not afraid."

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