Board games like scrabble and boggle are great for spelling and vocabulary development. Try to get them to say the definitions for the words (at least a brief one) rather than accept that they know them. Play with a dictionary at hand. Also ask them the meaning of the words you play so it seems that getting at the definitions isn't meant to just criticize/challenge their plays (which it isn't, the purpose is to develop their understanding).<p>Card games like Rook, Spades, Cribbage (mentioned elsewhere), Casino are great for math and pattern matching, planning ahead. These just require a standard deck of playing cards, maybe two (habit from playing Bridge, have one deck in play and one shuffled and ready for the next hand).<p>24 Game was a good one for arithmetic (4 numbers, put any of +, -, *, / between them and try to get the result to be 24).<p>Mastermind is another good strategy, logic type game. It can also be played with pencil and paper which makes it a very fun one to teach kids so they can play it anywhere.<p>Dots and Boxes is a nice abstract strategy game to play on paper, which can serve as a good gateway to other abstract strategy games.<p>Guess Who was a good game of logical deduction. Shades of 20 Questions where you ask for features of the person and mark off people who don't qualify. Clue, of course, is strictly a game of logical deduction if you can get past the movement mechanics and all (always frustrated me to get low dice rolls and not have a chance to win even when I knew or was very close to the answer). From Clue, books of logic puzzles that practice deductive reasoning from a set of facts (along the lines of Einstein's puzzle).<p>Others mentioned RPGs, these can be good with kids. Particularly if you focus the emphasis on teamwork (discourage showboating and hogging the limelight), storytelling (goes back to vocabulary, but also thinking about complex situations), planning and strategy. You can incorporate lots of puzzles into the game that emphasize wordplay (riddles and such) or math (numeric puzzles) or logic (colors, connecting their actions with specific effects) or just general problem solving.