ArtfulDodger: Just be carefull - a lot of times information like this for adults is good, but once kids read it - they think "Cool - I've got to try that" and puts new ideas in some kids heads.
(hide) If you want to play a game with an opponent of a similar level, you can define a required BKR range for a new game invitation. Then nobody with a BKR outside this range will be able to see/accept it. (Katechka) (show all tips)