Parents have heard how they need to be "confident and assertive for the sake of their children" after the Government made relationships and sex education (RSE) lessons compulsory.
The Marriage, Sex and Culture Conference 2021 held online this week brought together Christian campaigners and parents concerned about the new compulsory RSE curriculum.
It teaches about gender identity and different families as part of a wider curriculum intended by the Department for Education (DfE) to prepare young people for "life in modern Britain".
Christian Concern's Head of Education, Steve Beegoo, told the conference that parents should be "brave" in challenging what their children are being taught.
"Parents should be confident and assertive for the sake of their children," he said.
"We need to encourage that....they are the best people to keep their children safe and to educate their children and to be in charge of how their children are educated.
"Parents can and should ensure that education is in conformity with their beliefs. There is a law that they can stand on."
Article 2 of the First Protocol in the Human Rights Act enshrines the right of parents to have their children educated in conformity with their religious and philosophical convictions.
Statutory guidance on RSE says that lessons must be age appropriate, evidence-based, and take into account the religious background of pupils. Parents must also be consulted by schools on the content of lessons.
But concerns remain about the sexual content of some resources created for RSE lessons.
Voice for Justice UK founder, the Rev Lynda Rose, raised concerns about sex education lessons in a recent letter to Prime Minister Boris Johnson.
Replying on his behalf, schools minister Nick Gibb said that content for secondary schools "includes clear and accurate teaching about specifically sexual matters, and the need to teach about safer sex is firmly signalled".
"This also covers factual knowledge around sex, sexual health and sexuality, set firmly within the context of developing strong, loving relationships and resisting the pressure to have sex too soon," he said.
He added, "Our statutory guidance is clear that, in developing and teaching RHSE content, schools must take account of the age and religious backgrounds of their pupils."
Commenting on his reply, Rev Rose said it was "state-sponsored child abuse" to encourage children to question their gender and sexual identity.
"Yes, we do live in dangerous times and children are at risk, but whatever is being claimed, the aim of current policy is not child protection and safeguarding but is rather the promotion of an ideological agenda that's aimed at embedding behaviours that were previously regarded as hazardous, illegal and/or evidence of mental illness, which is why there are serious safeguarding issues which need to be urgently addressed if children in this nation are to be kept safe," she said.
She warned that RSE was normalising sexual activity among children and young people, while the emphasis on diversity was fuelling gender dysphoria and sexual confusion.
"Detailed and explicit teaching on the mechanics of sex without any kind of moral frame or guidance, encourages sexual experimentation and normalises promiscuity," she said.
"As part of the drive to teach safer sex, the message is drummed into children long before puberty that sex is great, when you're ready – which can be any time from 11 on, maybe earlier, if that's what the child wants.
"And they're taught that any and all kinds of sex are good, if both people involved are happy – so teaching covers vaginal, oral, and anal sex, as well as self-stimulation and fetishism, presenting all as absolutely fine, normal and on the same level."
She questioned why the Government was pushing sex education on young people when the statutory age for sex in the UK is 16.
"The impression now being given by schools is that if children are of similar age and they both want sex, that doesn't matter because it's all part of their sexual rights," she said.
"When you think about it, it's hardly surprising that in the UK, we have one of the highest teen pregnancy rates in western Europe and that STI rates amongst teenagers are, according to doctors, at epidemic levels.
"And the 14- to 25 age group is recording the highest rate in the country for new infections.
"The point to be made is that by normalising and encouraging sexual licence, schools are not only putting children and young people at risk; they are also encouraging young people to break the law."
She went on to say that even if such teaching were to take account of the religious background of pupils, it would only be with the intention of "undermining the tenets of that religion because what's being taught runs contrary to the teachings of all the world's major religions, which prohibit any and all sexual experimentation and relations outside of marriage".
The conference also heard from Dr Bernard Randall, who was reported to Prevent, the terrorist watchdog, after telling students at the Christian school where he was chaplain that they did not have to agree with LGBT ideology.
Supported by Christian Concern, he is taking Trent College in Derbyshire to court for discrimination, harassment, victimisation and unfair dismissal.
He warned that society was moving increasingly towards "totalitarianism" on LGBT issues.
"When I was accused of upsetting LGBT pupils and their feelings mattered, it didn't work the other way round and that's part of the problem with this ideology; it doesn't allow that there is a different worldview," he said.
"It doesn't allow [that] other ways of thinking and believing are acceptable. And as far as I can see, that's the dictionary definition of bigotry.
"A bigot is someone who is prejudiced and won't listen to reasons and won't accept there is another point of view.
"Christians are often accused of being bigots on this. I think the shoe is on the other foot, I really do.
"I think sensible Christians do listen and try to understand and avoid discrimination. That doesn't mean you have to accept and be wholly positive about certain decisions that people make."
He admitted it was an "odd position" to be in, to have been sacked as a Christian chaplain of a Christian school "delivering a Christian sermon in a Christian act of worship in a Christian chapel".
"And even very moderate Christian things," he continued.
"This was not hellfire and damnation or anything like that - a million miles from it. And it seems to me that this is an indication of how far the ideology wants to push society, that they want to say you must accept our viewpoint and that's kind of totalitarianism.
"Total control of everybody's thoughts and beliefs is the goal because that's the only thing they're going to accept. That's where we are. That's the world we're living in."
He asked for prayers, adding that it had been a "stressful time" for his family, and that "disappointingly" there had been no public support from the Church of England hierarchy.
"That shows there's a captivity of the Church rather than a sort of backbone conscience to stand up and be counted, which doesn't bode well on this issue," he said.
"But I think actually more widely for the Church, if we can't say this is what we believe and we think it's a really good thing, then what is the point?"
The conference was convened by the Marriage, Sex and Culture Group, which is part of Anglican Mainstream.