A common question in religious education (RE) lessons is, "Why do I need to study RE when I don't believe in God?"

This is an inevitable question, and my standard reply is to emphasise that 33 million people in the UK do. An estimated 80% of the world's population identify with a religious group and religion has a massive impact on humanity.

Nevertheless, the predominance of christianity in RE syllabuses – and the increasing secularisation of the nation's youth – poses a challenge for religious studies in non-faith schools. The 2011 census shows that Christianity has the oldest average follower age of the main religions in the UK, and that the number of Christians below 60 years old has fallen considerably. According to one survey, 65% of teenagers do not consider themselves religious.

It could be argued that the current framework for RE teaching needs to give more consideration to atheist and humanist world views to reflect society's beliefs correctly. The current statutory guidance for RE only requires the syllabus to reflect the religious traditions of Great Britain, which are Christian, and acknowledge the other "principal religions represented in Great Britain" – but not atheism or humanism.

Although most locally-agreed syllabuses allow for a limited presence of non-religious views, organisations such as the British Humanist Association (BHA), are campaigning for these views to be studied in more depth.

The RE Council of England and Wales is also carrying out a comprehensive review of the subject to coincide with the national curriculum review. Their draft has indicated that non-religious views could become central areas of study at key stages one to three. At the same time, Michael Gove has promised to "revitalise conversations on RE" and work with the Catholic and Anglican churches – "and others" – to improve the subject. Perhaps the "others" will include groups outside the main religious organisations.

In spite of these possible changes, an objection to the inclusion of further atheist viewpoints and humanism may simply be that they are not religions.

But their inclusion could fulfill other areas of the curriculum. Guidance states that RE "provokes challenging questions about the ultimate meaning and purpose of life, beliefs about God, the self and the nature of reality, issues of right and wrong, and what it means to be human." To do this effectively, humanistic perspectives on these topics must be considered. Moreover, challenging questions about God will be enhanced with reference to atheist points of view.

Another key element here is community cohesion. Guidance states that RE "provides a key context to develop young people's understanding and appreciation of diversity, to promote shared values and to challenge racism and discrimination." If shared values are to be promoted, however, secular values must be accounted for, otherwise we are bypassing the values of the 65% of students identified as non-religious in the survey mentioned above.

I don't think that Christianity and other religions should be constantly compared with and challenged by non-religious views. There is still a need to study the founders of the six world religions, their beliefs, practices, ethics and teachings. This is the bulk of what RE will always be. Nor am I suggesting that faith schools need to challenge their students every time there is an act of collective worship or discussion on religious doctrine.

But in non-faith schools it is best if RE includes the views and opinions of atheists and humanists, even if this seems oxymoronic; secularisation affects religion as much as religion affects society.

Andrew Jones is head of religious studies and sociology at Goffs School in Cheshunt, Hertfordshire. Find his department website and on Twitter as @GoffsRS. Andrew is also a teacher adviser to the Guardian Teacher Network.

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