My three year old neice came to visit this weekend. She spotted my chess set and asked to play. She assured me she know how to play. So we got the set out and settled down on the floor. I wasn't convinced that she knew the rules, so I got her to set the peices up. She randomly plonked peices on various squares, then asked me where the ball was.
"the ball for knocking the peices over with"
Not having a ball was no obstical to her knocking the peices over.
Then we set them up again and took turns knocking them over one at a time.
Best chess game. Ever.