It works like this: you have a deck of cards that each have a Chess piece on them, with instructions and a picture explaining how that piece moves. Flip over a card, move a piece. You quickly learn how all the pieces move and how to strategize. Then you put the cards away and play for real once you're confident. I love it! And my kids are learning logic and strategy, but don't tell them.
So after falling in love with this medieval game of logic, I found "The Kids Book of Chess" on Paperback Swap. It explains why the pieces move the way they do. It tells the story of Chess. For instance, did you know that pawns capture diagonally because the real pawns (foot soldiers) carried shields as big as they were, so they couldn't see in front of them. They had to strike from the side. Very cool! The kids all really enjoyed the battle tale.