In the ramshackle industrial hinterland east of Bristol Temple Meads station, four circus performers are giggling with delight as they as they take turns doing handstands, spinning hoops and juggling clubs.

One of the performers keeps fiddling awkwardly with his shorts as he throws a multitude of hats towards the skylights in the warehouse roof.

The other three try to guess his what secret instruction the director has given him: “Do you have wedgie?” “Are you wearing a tiny thong?” “I thought you were trying to hide an erection.”

This is an early rehearsal for what is thought to be the country’s first sexual health circus. The performers – Jess Herman, Jacob Hirsch-Holland, Emily Ball and Winston Pyke – and director Robyn Hambrook have received £20,000 of funding from the Arts Council and the Paul Hamlyn Foundation to bring the show to Bristol schools starting this month.

Last week, MPs voted to make relationships and health education (RSE)compulsory in all schools, and sex education mandatory in secondaries.

Drawing on the new RSE curriculum, the circus initiative aims to explore the issues that sexual health charities say are often neglected in schools, such as healthy relationships, sexual pleasure and LGBT relationships.

Herman, who came up with the idea for the show while working as a sexual health adviser in the city, says too many youngsters are ill-prepared. “Young people do not have enough high-quality relationship and sex education to equip them for the challenges they come across on that road of adolescence,” she says, cradling a mug of herbal tea in a rare break from the rehearsals. “Hearing 15- or 16-year-olds being really unclear about consent is worrying. I’ve had to tell some young people that the sex they have had is not consensual.”

A survey by the youth sexual health charity Brook found that 56% of mainly first-year university students had received unwanted sexual attention, but only 15% realised that these behaviours counted as sexual harassment. The same survey revealed that half had not received any information about consent and only a third had learned about harassment during RSE lessons.

Herman, who is 35, also wants the circus to show the positive side of sex and relationships. She says schools do not always acknowledge different sexualities or make space in busy timetables for young people to learn about healthy relationships – although she accepts that may change with the new curriculum.

“Traditionally it would be about a man having sex with a woman and not getting her pregnant,” she says. “But I’m always talking to young people about any gender having sex or being physical with any gender – and about asexuality too. Young people are thirsty for knowledge about how to make relationships fun, enjoyable and pleasurable.”

Under new guidelines, all secondary school pupils will receive compulsory RSE from 2020. They will learn about the benefits of healthy relationships as well as the dangers of sexting, grooming and FGM. However, parents will have a right to request that their children be withdrawn from sex education, and schools will be able to take into account religious backgrounds.

Lisa Hallgarten, head of policy at Brook, welcomes the fact that sex education is becoming mandatory, as provision is currently patchy. “The majority of schools are doing the minimum they can get away with,” she says.

But she warns that the guidance has too many caveats. “It gives schools a huge amount of latitude. There is a danger that it’s not going to provide universal good-quality sex education for all.”

Yet some parents are unhappy about it happening at all. A parliamentary debate was held last month after more than 100,000 people signed a petition against mandatory RSE, claiming that the curriculum was harmful and parents should be allowed to deliver RSE at home in their own way.

Later that evening, Herman is running a workshop near the city centre at which 11 local teenagers will discuss their experiences of RSE. Their opinions will shape the final show.

George Jones, who has just turned 18, says he was not taught anything about gay relationships. “As I was growing up, I knew I was gay but I thought I wasn’t into gay sex. Then I found out that’s not how it works. Because of that I struggled so much,” he says. “I had to find out entirely by myself. I’m still kind of clueless.”

Frankie, also 18, says her school did not prepare her for manipulative partners. “I found myself in that situation and I had no idea how to deal with it,” she says. “I felt a bit lost and very much on my own.”

Evie Basch, 20, who identifies as non-binary, was left feeling isolated because school lessons centred on heterosexual sex. “It wasn’t realistic and it was very straight-focused. It didn’t take into account that some people in the class might be queer,” Basch says.

Herman is excited by the prospect of bringing her circus to the city’s schools but accepts that some parents will withdraw their children. “I’d much rather they didn’t, because the children will miss out,” she says. “The earlier young people can have honest and real relationship and sex education, the better-informed they are, and the more they are able to make positive choices for themselves.”