simple rules for non-gamers

My boss just asked me for advice regarding a simple set of rules 
suitable for his children to play with (ages 7/9).  He's not a gamer, so

I'm wondering if anyone knows of anything that might be suitable. 
Probably WWII or SF.

Andrae

-- 
  Andrae Muys	 <andrae.muys@braintree.com.au>
  Engineer	 Braintree Communications
  "Now lets say ... I do something stupid making it no longer possible
   for me to run b@p.  For example the computer has been run over by a
   truck while sitting out on the curb during an ice storm."
       seen on erlang-qustions.