When I brought my children to Japan a year ago, I expected they'd pick up on certain things faster than me. I did not, however, anticipate that they'd so quickly succumb to the Japanese national obsession with janken.
Granted, janken is not unique to Japan. As a kid, I occasionally played the Western version of the game, which we called "rock, paper, scissors." On hot summer evenings, we kids would stand in a circle. At the count, everyone put out a hand sign for rock, paper or scissors. Rock beats scissors. Scissors beats paper. Paper beats rock.
We played for maybe five minutes before everyone lost interest. Then we'd move on to something better, like "capture the flag."