Lessons will also focus on Druids and Rastafarianism as part of a syllabus designed to boost understanding of religious diversity around the world.
Attitudes by different faiths towards same sex marriages, human rights, gender equality and even GM crops will be among the topics covered.
The course will largely snub traditional lessons on the Bible and other holy books.
Examiners said the syllabus - by one of Britain's biggest exam boards - will make the subject more "relevant" to students.
But it has been criticised for "pandering to popularity".
Religious studies is currently one of the fastest-growing GCSEs in the UK and in the last two years the number of entries has increased by 24,000 to 171,000.
From September, the OCR exam board will run three courses.
Religion and Belief in Today's World - one of the syllabuses - will "challenge students to think about the role of religion in modern Britain and in the worldwide community".
One topic will focus on how atheism has been marked in countries around the world. This includes the influence of the British Humanist Association, which recently backed an advertising campaign proclaiming "There's probably no God", and the work of best-selling author Philip Pullman in the UK.
In other subject, pupils will investigate different religious attitudes towards genetically-modified food, cloning and medical ethics.
Another topic asks students to study perspectives on relationships, including forced marriage, inter-faith marriage and same sex couples.
In one key area, lessons will focus on the influence of minority religious movements, such as Falun Gong, the banned Chinese spiritual group, and the Order of Bards, Ovates and Druids, which believe in the spirituality of nature. As part of a topic on Rastafarianism, students are asked to look at the influence of Bob Marley in the 1970s.
Liam Gearon, professor of lifelong learning at Plymouth University, who supports the new course, said: "This is an intellectually exciting new GCSE which will challenge students to think about the role of religion in modern Britain and in the worldwide community. Encouraging the use of historical reflection as well as thought-provoking analysis of contemporary events, it will engage students of all abilities with the many issues that surround religion in the modern world."
The disclosure comes days after another exam board - the Assessment and Qualifications Alliance - announced it would run a religious studies GCSE in which pupils answer questions about homosexuality, conservation, binge drinking and drugs in sport.
Anastasia de Waal, head of family and education at the think-tank Civitas, said: "We seem to be so desperate to make things relevant - to pander to popularity - that our kids aren't being taught the underlying knowledge they need to succeed in the world. We are doing a huge disservice to our young people."