The things that deconverted me as a child:
- National Geographic Concise History of Religions: Either one of these is right, and it's not yours, or none of them are right. I'm particularly fond of the Aztecs, since they believed at a depth no rational person can comprehend… and were just totally wrong. Huitzilopochtli didn't end the world when the sacrifices stopped.
- Carl Sagan's Cosmos, book (most importantly) and TV series (often streaming online, or get the boxed set). Explains the scientific method, and how we have learned what we know. I don't recommend Neil Degrasse Tyson's version, which is much more pop-culture.
- Isaac Asimov's Guide to the Bible: Explains where the Bible came from and how it was written, and why.