The Chief Rabbi, Ephraim Mirvis, is leading protests against plans to change the Religious Studies syllabus to make it compulsory for pupils to learn about at least two world religions.
Community leaders told the Jewish News that forcing pupils at faith schools to learn the details of a different religion than their own would be like forcing German-language students to learn Spanish. Currently they must just learn one, usually their own faith.
The Mail on Sunday revealed last weekend that the new Education Secretary Nicky Morgan wants Religious Studies students to gain "different perspectives" on faith.
She wants to broaden the syllabus in response to the so-called "Trojan Horse" scandal in Birmingham. The scandal affected secular state schools, not Muslim schools. The alleged plot by radical Muslims to take over schools in Birmingham led to new Government measures to make schools teach traditional "British" values such as tolerance.
Home Secretary Theresa May backs Morgan's plan but Communities Secretary Eric Pickles opposes it.
A spokesman for the Partnership for Jewish Schools told Jewish News the move would "likely impact on performance in a subject which is already being marginalised in many schools".
The spokesman added: "The introduction of an additional religion in RS GCSE is like incorporating Spanish into the German GCSE and our teachers feel that GCSE examinations are not the right medium to promote a Government's agenda."
Chief Rabbi Mirvis and Board of Deputies' Senior Vice-President Laura Marks said that while the objective is admirable, compelling faith schools to teach another religion would backfire.
"I enthusiastically support efforts to ensure British values are taught to all," said Mirvis. "But forced changes to the GCSE, through which so many learn about their own faith, is not the right way to achieve these shared goals."
Marks said: "Making it a requirement is just one way to do it, but there are other ways too, such as twinning, cultural events and talks from faith leaders. What suits one school might not suit another. Making it a requirement could quickly prove counter-productive. The aim is not to turn out children who understand Islam, but to promote tolerance and to have children who understand the world and who can interact with it. We share that aim."
However, senior Reform Rabbi Laura Janner-Klausner said: "It is vital that in a multicultural society children learn about other religions. This applies to all communities including our own."
The Catholic Archbishop of Westminster, Vincent Nichols, is also concerned.
The Archbishop of Canterbury, Justin Welby, is understood to be broadly supportive.
Chief Rabbi Mirvis is expected to raise his concerns with the Prime Minister David Cameron in a meeting soon.
