A vast majority of the population believes religious schools should not be allowed special dispensation over the national curriculum, according to the results of a YouGov poll for the JC.

Asked whether state-funded faith schools should be allowed to refrain from any form of sex education in lessons, a massive 82 per cent said no. Only nine per cent believed the schools should be given the freedom to leave out lessons on sex.

Over two thirds of those questioned, 67 per cent, rejected the idea that faith schools should be allowed to teach creationism — “that the world was created in broadly its present form by God” — as a legitimate scientific theory on a par with evolution. Only 18 per cent agreed that they should.

Opposition was uniformly high across gender, age, class, region and political affiliation.

The results are likely to intensify fears among Charedi educational leaders that strictly Orthodox schools might have to leave the state system if they are pressured to teach subjects incompatible with their religious values.

Orthodox educators are increasingly concerned about lobbying by secular groups.

Jonathan Rabson, executive director of the National Association of Jewish Orthodox Schools (Najos), said: “We fear the day that the high-performing Orthodox Jewish schools will have to withdraw from the state-maintained sector in order to safeguard the wishes of parents to protect their children from exposure to subjects that run counter to core religious beliefs.” The poll results come in the wake of the ruling by the exam regulation body Ofqual that schools may no longer block out exam questions thought unsuitable for pupils. It emerged that one state-aided Charedi school had redacted a GSCE science paper last summer.

Vocal opposition to exemptions for faith schools has come from groups such as the National Secular Society and the British Humanist Association.

Rabbi Avraham Pinter, principal of the state-aided Yesodey Hatorah Girls High School in North London — which blocked out a science question last year — said of the poll results: “We live in a free country — people are entitled to their views. I think that everyone should appreciate that other people have different views — that’s what we’re asking for.”

Most Charedi schools in areas such as Stamford Hill remained private because of concerns about the national curriculum, he said.

“I think the government in the past has been giving out messages that they want to see more schools like ours joining the state system, but they would need to create a situation in which they would feel comfortable.”

According to the national curriculum, schools have to teach about human reproduction in secondary school science.

From September, evolution will become a compulsory part of the primary school science curriculum in state schools.

Rabbi David Meyer, executive head of the Orthodox Hasmonean High School in London, said he was proud that his school taught evolution and reproduction.

But he was nevertheless troubled about the recent move by Ofqual.

“I think it is a worrying development that certain schools are being forced to teach in a way that they are not comfortable with,” he said.

Mr Rabson said: “Although Najos will clearly be advising schools not to ignore the new Ofqual guidelines, we see this reversal as a direct attack on parental choice.”

He added: “As the Department for Education appears to have strayed into the teaching of science and morality that are traditionally the domain of religious education, it is becoming increasingly challenging for strictly Orthodox schools to maintain an adherence to the detail of the national curriculum.

“In our experience, local authorities and [inspection body] Ofsted have always respected the school’s delivery of the national curriculum within the guidelines of religion if there is a robust policy to support it.”

Fertility expert Lord Winston commented: “The idea that Jews should shut themselves down from what might be a question of science or any factual observation about the possibilities of the natural world seems to be entirely illogical.”

Schools that are troubled by such topics can switch from voluntary-aided status to become academies, which are not bound by the national curriculum.