Irena, you might also be interested in "Your Fantastic Elastic Brain". It's a picture book but is aimed at slightly older kids because it talks about the anatomy of the brain and how it works. The book's main emphasis is that you need to try new things and make mistakes along the way if you want your brain to grow. I found it useful with DS6 who is an extreme perfectionist and is horrified at the notion of making mistakes. I presume most GCs are pretty cerebral, so it might help for him to understand that mistakes can actually be a "good" thing.
