By Robert Pigott
Religious affairs correspondent, BBC News
There are plans for more camps at Easter and in the half-term holidays
An atheist summer camp in Somerset is offering children aged seven to 17 a "godless alternative" to religious camps traditionally run by the scouts and church groups.
Some of the 24 children arriving at Camp Quest in Bruton seemed a little young to be tackling the weighty concepts ahead of them.
The summer camp, designed with the children of atheist parents in mind, has a slightly daunting mission statement.
It is "dedicated to improving the human condition through rational inquiry, critical and creative thinking, scientific method
and the separation of religion and government".
Certainly the Murray boys - John, Julius and Leeroy, aged nine, eight and seven respectively - were focusing on the simple pleasures of living under canvas for five days and taking part in traditional activities like climbing, canoeing and rafting.
John said: "I'm looking forward to making new friends, meeting new people and doing all the activities set up for us."
Leeroy noted: "I like activities because it will give you more health, and you will be quite fit for running the 200 metres."
While Julius added: "I like sleeping in sleeping bags because it's nice and cosy and it covers the whole body."
The 24 children were housed in a dozen brown and green tents grouped around a camp-fire on a sloping grassy meadow fringed with trees.
Camp organisers say they tell children "how" not "what" to think
The rafting got off to a noisy start as teams of six took to the waters of the River Brue on crafts they had constructed from blue plastic drums and planks of wood.
Among other early activities was an obstacle course including rubber tyres and netting which the children completed blindfolded.
The camp sets out to teach co-operation, tolerance and empathy. But it is the approach to life's bigger questions that sets it apart - especially its treatment of religion.
Its website describes a sceptical approach, stating: "Campers are taught that ethical behaviour is not dependent on religious belief and doctrines, that religious belief and doctrines are sometimes a hindrance to ethical and moral behaviour, and that irreligious persons are also good and fully capable of living a happy and meaningful life."
The camp's director, Samantha Stein, insisted it was intended to get the children to think for themselves.
She said: "If the children were to come up with a question about creationism for example, we would discuss the evidence. We wouldn't say, 'Creationism is rubbish'
if they weigh the evidence and think there's a good case for it."
Most mainstream Christians would not include creationism as part of their faith, and would also encourage the "rational inquiry" suggested by Camp Quest.
At least one of the parents delivering children to the Mill on the Brue activity centre had already taken his daughter to one of the many Christian summer camps, but wanted to give her wider experience.
The father of the Murray boys, also called Leeroy, said he would also be happy to take them to a Christian camp.
He said: "The biggest thing here for me is to give them a range of experiences and to encourage them as far as possible in understanding religion and to understand science and to give them the tools for them to make up their own mind which direction they want to go."
Fellow parent Crispian Jago also endorsed Camp Quest's aim of getting children to think for themselves.
"Anything that can teach the children ways of thinking critically, ways of examining arguments, and recognising logical fallacies and trying to determine for themselves what they believe is true, then I think that's a positive thing," he said.
The camp insists that when it comes to God, it is not telling the children what to think so much as how to think.
Camp Quest was born in the US 13 years ago, as secularists sought an alternative in a summer camp market dominated by religious institutions.
The British version is costing participants £275 for the five days, and there are plans for others, at Easter and during half-term holidays.
By evening the uncertain weather had produced a number of sharp downpours and by sunset there was a definite chill in the air.
But the children gathered round the camp-fire with their enthusiasm undimmed, to be set their principal task of the week.
For the "centrepiece" of its scientific approach to religion the camp asks its participants to search for two invisible unicorns.
The unicorns cannot be seen or heard, tasted, smelt or touched, they cannot escape from the camp and they eat nothing.
The only proof of their existence is contained in an ancient book handed down over "countless generations".
A prize - a £10 note signed by Professor Richard Dawkins - is offered to any child who can disprove the existence of the unicorns.
Outside the camp gates, a single lonely demonstrator criticised both Professor Dawkins and the camp he supports.
Paul Arblaster, the chaplain of a non-denominational church in the small cathedral city of Wells in Somerset, was holding two home-made placards.
He claimed the unicorn story showed that the camp did not limit its teaching about religion to neutral "rational inquiry".
"Certainly I think there's a slant on it. They may deny that the unicorn exercise is anything to do with God, but I think it's a fairly thinly-veiled representation of that sort of indoctrination," he said.
But Ms Stein denied the claim, saying: "The object is not to bash religion or to tell the kids that there's no such thing as God. The object is to get the kids to think about things like the burden of proof.
"So, who has to prove the unicorns are there... is it the person who says they are there or is it the person who's saying, 'No, I don't think you're right'?
"So it's really a way of trying to get the kids involved in philosophical thinking but in a way they don't realise they're doing it."