My kids are 5 and 3 years old. I would like to teach them chess by playing alternative mini-game. Where can I find those mini-game instruction?
If your just looking for instructions, here is the wiki on mini chess. Make sure you checkout the external links.
To take Andrew's comment a bit further, I will give my own experience with my 3.5 year old. This is what he knows now with limited time. He can name all the pieces and he can set the board up, but that is about it. If I ask him to move the bishop, he will swipe it across the board, but that is OK. He does not have the concept that it is a game for two people and I am black or white (every piece is his :) ) Your 5 year old probably will get a better grasp on mini chess, but 3 may be too young for it.