I have been very conscious lately of making sure I encourage the kids to question things without being afraid of being chastized or outed in some way by their peers/elders. Even as an adult I sensor myself in front of certain people to avoid a mark on my proverbial forehead in my small town. It sucks, but it's called survival. I definitely want my kids to feel like they are able to question without judgement at home, if nowhere else.
So I found this book by Hyman Ruchlis: How Do You Know It's True?: Discovering the Difference Between Science and Superstition
This is great reading for ages 10 + and prompted a few good discussions about things that we may take for granted even though they really make no sense.
Growing up in a Roman Catholic/Italian family, I've heard my share of superstitious notions. Some of my relatives like to try and implant those seed in my children's' grey matter. This is one of those books that has helped break down and sort out all that nonsensical thinking. It' well written and easy to understand.