Simon Says
http://www.mathsisfun.com/games/simon-says-game.html
Try to remember the shapes or numbers. I great game for younger children to sharpen their memory skills as they flip cards.
http://www.netrover.com/~kingskid/memory/memorize.html
http://www.nabiscoworld.com/Games/game_large.aspx?gameid=10038
Chess Rules - http://www.chessclub.com/resources/rules/