The first national framework for teaching religious education in English schools has been published.
The Qualifications and Curriculum Authority says pupils should study other faiths alongside Christianity to help foster understanding and respect.
The government-backed framework is not compulsory, which disappoints the Church of England, though it is pleased at the emphasis on RE for all.
But the National Secular Society called it a "charter for indoctrination".
'World views'
The Education Secretary, Charles Clarke, launched the framework on Thursday.
Christianity is still the main religion featured.
However, it recommends studying the tenets of the other five main religions - Buddhism, Hinduism, Islam, Judaism and Sikhism - across the school years up to the age of 14.
And it says it is also essential that pupils are able to share their own beliefs without embarrassment or ridicule.
So it recommends there should be opportunities to study other religious traditions such as the Baha'i faith, Jainism and Zoroastrianism, and secular philosophies such as humanism.
Atheism is not mentioned in the guidance, which is for all pupils aged three to 19.
Mr Clarke said: "Faith groups must seize this opportunity to develop their own resources that enhance understanding of their faith, and their response to world issues. I support the development of materials that can be used with the framework.
"Religious education can transform pupils' assessment of themselves and others, and their understanding of the wider world. I see it as vital in widening inclusion, understanding diversity and promoting tolerance."
'Balance'
Canon John Hall of the Church of England's National Society for Promoting Religious Education said it had hoped Mr Clarke could have been persuaded that the framework should have been statutory.
"We hope it will have a statutory effect," he said - meaning that a large majority of schools would adopt it.
"My guess is it's going to have a strong wind behind it."
He was most pleased that the framework advocated the teaching of RE for everyone, right up to the age of 19.
Canon Hall said he had been disappointed that last week's Tomlinson report on 14 to 19 learning in England had been "weak on RE".
"This resets the balance and we welcome that."
Questions
However, Keith Porteous Wood of the National Secular Society said: "In the past we have discouraged parents from absenting their children from religious education classes, as is their right under the Education Act, because we had received reports of children being made to sweep school playgrounds as an alternative, and being isolated from their peers.
"But now, after seeing this report, we feel strongly that non-believing parents, who are anxious that their children receive balanced, objective teaching about religion, will not be well served."
At one point the document said pupils should be "encouraged to reflect on the important contribution religion can make to community cohesion and the combating of religious prejudice and discrimination".
"We want to encourage community cohesion," he said, "but the evidence all around us of sectarian warfare and hatred tells us that the QCA approach flies in the face of reality."
Elsewhere in Britain
Local authorities in England have previously written their own guidelines for religious education.
By law, schools have to teach RE but parents have the right to withdraw their children from all or part of the lessons, even in church schools.
The school is not obliged to provide alternative lessons for those children.
In Wales, schools are encouraged to teach children about "Christianity and the other principal religions in Great Britain" but there is no mention of secular philosophies.
Scotland's national guidelines on religious and moral education (RME) say that, "while recognising the role of Christianity as the major religious tradition in Scotland, pupils should also be encouraged to develop understanding of and respect for people of other faiths and people who adopt a non-religious stance for living".