Educational puzzles, brain teasers, mathematical recreations and word games. A resource for anagrams, cryptograms, alphametics, word puzzles, logic problems, doublets, tangrams, chess, and math quizzes. http://www.logicville.com/
Printable puzzles and other diversions to help substitute teachers involve their temporary students in mind stretching activities. http://www.subhelp.com/
Pictographic puzzle microcosm of old and new playing cards, poems, games and lore. New suits: the zodiac, solar system, evolution, human family, ancient elements, astronomical basis of the calendar and compass. http://www.cosmicpuzzle.com/
Contests of varying difficulty and types. Also has tutorials with worked examples and practice games. [Registration required] http://www.puzzletome.com/