An exercise: rank the various different elements involved in keeping children safe and ensuring that they are well-prepared for adulthood.

Is establishing good friendships more important than knowing how to avoid sexually transmitted infections? Is it more or less important to be media-literate than to know the names for your own body parts?

This is the situation that teachers and sex-education campaigners find themselves in. And they fear that the result will be a watered-down sex-education curriculum.

The government has issued a call for evidence on relationships and sex education (RSE), asking teachers, campaigners, pupils and parents to respond to a series of questions. Specifically, respondents are asked to name the “three most important subject areas” to be taught to different age groups.

“You can’t just say, ‘We’re going to cover sexually transmitted infections, consent and friendships,’” says Lucy Emmerson, national coordinator of the Sex Education Forum. “None of those, taught in isolation, will suffice.”

This is echoed by the PSHE Association, which lobbies for the subject and represents its teachers. “Relationships education is about equipping children to navigate real-world experiences,” says Jonathan Baggaley, the association’s chief executive.

“I worry that people will say, ‘The most important topics right now are: online pornography, mental health and consent,’ and we’ll end up with something that makes no sense, and also is driven by current trends.”

Meanwhile, there are broader concerns that a fear of controversy will lead to the government shying away from the specifics of sex education, in order to fend off potential critics.

The law introducing statutory sex education was passed last April, when Justine Greening was education secretary. “Justine Greening was a fantastic champion of this,” says Sarah Champion, former shadow secretary of state for women and equalities, and one of Parliament’s most vocal advocates for sex education. “She understood that it makes people feel they have rights from a very young age.”

Nervous and squeamish

Greening’s first appearance in the House of Commons after being replaced as education secretary was to press the government to work with Champion and Maria Miller, chair of the women and equalities select committee, to ensure that there was cross-party support for any sex-education guidance published by her successor.

“Justine Greening’s appearance in Parliament - that’s what started to spook me,” Champion says. “If she’s nervous, we’re nervous.

“My concern is that, rather than looking at things like online abuse, sex education will get watered down to British values and tolerance. That would be negligent of us - to throw that away, because you’re anxious that you might offend an adult.”

Champion’s interest in sex education is driven by the fact that she is MP for Rotherham, where 1,400 children were revealed to have been victims of sexual exploitation during the years between 1997 and 2013.

Good sex education, she says, is vital to prevent such incidents in the future.

“Rather than dealing with the consequences of abuse, how do we prevent abuse?” the Labour MP says. “We need relationships education for primary children. A lot of children don’t realise they’ve been abused until later in life.

“These are uncomfortable things. I understand people’s nervousness around this. But, for me, child protection must overcome the squeamishness that people have about difficult subjects.”

Specifically, campaigners are concerned that the views of conservative faith groups will mean that schools deliver a toned-down version of sex education that deals only in generalities.

Government legislation says that sex education “should be appropriate to the faith” of pupils.

“They haven’t quantified what ‘appropriate’ means,” says Emmerson, of the Sex Education Forum. “What we don’t want is schools to think that, because of their local community, they don’t have to think about sex education. Or: their parents are from a particular faith, so we’re not going to teach about this.

“We’d say that the whole of RSE is appropriate to all faiths. You can’t leave things out, or not teach RSE. The real risk is that some schools will say ‘Our community doesn’t want this.’ That would be retrogressive.”

Recently, Lord Singh of Wimbledon - invited by the Department for Education to give a Sikh perspective on relationship teaching in schools - told Parliament that he was “appalled at the undue emphasis on sexual relationships and sexual identity currently being taught”.

“Young children are led to questioning their gender and, unhelpfully, offered support to make permanent their potential differences,” he said. “Parents and teachers should have a right to question or opt out of such teachings.”

Parents do already have the right to withdraw children from sex-education lessons. No national figure is available, but the figure for parental withdrawal from sex education in Catholic schools is just 0.01 per cent: equivalent to one in every 7,842 pupils.

The government has said that parents would have the right to withdraw their children only from the sex element of RSE. But campaigners fear that would force an artificial split further watering down the subject.

“What does it mean?” one campaigner, who asked to remain anonymous, says. “Will your kid be in half the class? It’s a sop to parents.

“Some will argue that this is a fundamental rebalancing of the relationship between state and family - they need to be reassured.”

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