My son started going to Sky Ranch (Van, Texas....east on I-20) when he was in 2nd grade. He went every year and when he was 15, he became a junior counselor. He is now 25 and he has talked about being a full time summer counselor there, because it meant so much to him. It is a Christian based camp, but it is not any specific denomination.
http://www.skyranch.org/
It is really a neat experience - boating, rafting, canoeing, riflery, archery, horseback riding, swimming, evening events, etc. I recommend it highly. You can check out the website. It costs a bit, but it is well worth it.