Tonight, we look at atheism in america. There are tens of millions of nonbelievers in the country. The number has more than doubled in the past two decades, so little surprise there is a new movement.... See More
Tonight, we look at atheism in america. There are tens of millions of nonbelievers in the country. The number has more than doubled in the past two decades, so little surprise there is a new movement. The separation of church and summer camp. A wave of atheist camps offers a god-free alternative to religious camps. Lindsey davis has a look inside. Reporter: He has a summer ritual. A week away from home in washington state to attend atheist camp. Why don't you believe in god? Well there is no proof that god exists. Reporter: To it's actually called camp quest. It's where hundreds of nonbelieving parents send their fspring. This is ella, age 9. If he were to come down and do something really amazing, i would be able to accept that he exists. Reporter: Heady stuff for summer camps. You guys are united here in your nonbelief. Yeah. Reporter: But it's time to spend time with people like them ssms. I don't have any atheist friends. I would like have go to a friend's house and have dinner and not have to pray. All my friends are christian. Sometimes I do get bullied because of that. This is really sumer nice to be here and not have to limit yourself. And no that you will not be bullied or hurt. Reporter: The camp rents the camp from another camp. So masking tape hides the world of lord or god. In a lot of ways, religion and science share a motivating force. Reporter: They are socrates cafe where they are free to discuss whatever is on their mind. I don't need somebody to pray to. I just find a way myself. Reporter: Do you they whatever your pampbts are, you become. My parents, their parents were religious. And they became atheists. Reporter: But sierra's 12 and she's never believed in god. Don't you have to be exposed to it. Some of my family is catholic. I have gone to a wedding and funeral. Understand why they want to believe in something like that. But I don't really understand it. Reporter: They are not alone. According to the 2008 census, more than 34 million americans don't believe in god. In just the last two decades, the number has more than doubled. Reporter: Some people say, you guys are brainwashing these kids and we want them to decide for themselves. We would encourage them to go to church. The best way to become an atheist is to study the bible. Reporter: This woman studies effect of spirituality on children. Health, and great importance to teens, meaning and purpose. Reporter: It started in 1996 in kentucky with just 20 campers. This is the 13th camp quest location, and this year, they have more than 620 campers. Parents like chandler's father matt, who was raised jewish, and his mother, raised christian, both now atheists. If our children want to be jewish, fine, we would love them. We just wanted them to be good, happy people. Reporter: Chandler did admit he is not above sneaking a look at the good book. Sometimes in hotels they have a bible in the drawer and i think once I have opened it and looked at it. But just a little curious. What was in it. Reporter: And elle says she was 3 when her family dropped out of the mormon church. The first three years of my life I was raised at mormon and they didn't want to go to church anymore. And so we became atheist. Reporter: But elle said she thought a lot about why people believe in god. Think they are scared of the unknown. What if something very, very terrible happens and they don't have someone to come in and help things out and make things better. And I think they are scared of not having that. Reporter: Elle, for one, is still working on our secular philosophy. What do you hold on to if something bad happens? Really, I don't know. Reporter: You are still trying to figure that out? Yeah. Reporter: For "nightline," I'm lindsay davis, in
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