Children will be taught about atheism during religious education classes under official plans being drawn up to reflect the decline in churchgoing in Britain.

Non-religious beliefs such as humanism, agnosticism and atheism would be covered alongside major faiths such as Christianity or Islam under draft guidelines being prepared by the Qualifications and Curriculum Authority, which regulates what is taught in schools in England.

Although some schools already cover non-religious beliefs, there is currently no national guidance for what is taught, even though all schools must provide religious education.

The draft plans being drawn up by the QCA will not be compulsory, allowing religious schools the freedom to keep devout parents happy. But they will be regarded as best practice for heads, and are likely to be followed across the country.

A spokesman for the QCA said its guidance would be released for consultation in the summer term, but added: 'It is very much the intention that young people in the context of religious education should be studying non-religious beliefs. There are many children in England who have no religious affiliation and their beliefs and ideas, whatever they are, should be taken very seriously.'

The plans risk sparking a conflict between evangelists, who want to strengthen faith teaching, and secularists, who argue it is becoming irrelevant to modern life.

The first shot in the debate will be fired with a controversial report to be published tomorrow calling for RE to be renamed religious, philosophical and moral education and children encouraged to debate such ethical issues as whether it is permissible to express racist views.

'The whole thing is terribly biased in favour of religion right now - it's all about encouraging an identification with religion,' said Ben Rogers, author of the report for the Institute for Public Policy Research thinktank.

'There are huge numbers of people who are atheists or whose families are atheists and who are coming into a class where their family's view is not acknowledged. You should be able to have a conversation about ethics that doesn't collapse into a conversation about religion.'

While 19 per cent of Britons attended a weekly religious service in 1980, by 1999 that had fallen to 7 per cent - prompting some to argue that RE should be scrapped as a compulsory subject. Secularists say there is little point trying to drum religion into sceptical children at school.

'We're not trying to suggest that nobody should learn anything about religion: it is part of our culture and informs our art and our literature,' said Keith Porteous Wood of the National Secular Society, which has written to Education Secretary Charles Clarke calling for atheism to be included on the syllabus.

'But if you try to teach morality through "the Bible says" or the Ten Commandments, most children won't accept it as they don't believe the religious message. It would be much better if people learned morality by looking at current examples. It's philosophy that we really want to be teaching.'

Religion in schools is a sensitive subject, with France renewing a ban on the wearing of the hijab while in Britain it emerged last week that a Luton schoolgirl had launched legal action after being sent home for wearing traditional dress.

But Rogers said that trying to keep religion out of schools would not work: 'It won't make religious strife go away - if anything it will exacerbate it. Religious education can play an important part in combating prejudices.'

If non-religious beliefs were included in classes, parents should lose their current right to withdraw pupils from RE lessons, Rogers said.