Kids are very curious and by their nature if they dont get an answer they will try and find it themselves. There are definitely ways to sanitise things so they don't get the gory details but still get enough knowledge to satisfy their curiosity.

Like Kevlegs, I was very curious about history and loved it in school when I was a kid, I also talked a lot with my Grandfather who was like a second father to me growing up, always educating me about maths, history, geography, politics etc..

I'm sure there are Swiss school books out there that allow a child of that age to read up on events such as WWI and WWII..

IC