Brain Teasers and Math Puzzles  
   Interactive puzzles to challenge logic and mathematical skills. Immediate feedback with detailed solutions is provided.
   http://www.syvum.com/teasers/

Figure This! Math Challenges for Families  
   Assortment of mathematical challenges based on real life situations.
   http://www.figurethis.org/

Math Cats  
   Games, crafts, art, and story problems featuring cats. Encourages children and teens to enjoy and explore mathematical concepts.
   http://www.mathcats.com/contents.html

Math-Kitecture  
   Be a master architect. Draft a floor plan using software as you learn math, or try other fun "architivities." Designed for middle school students.
   http://www.math-kitecture.com

Maths Is Fun  
   Includes lessons, games, puzzles, and offline activities.
   http://www.mathsisfun.com/

The Mathsfile Game Show  
   Hosted by the ancient mathematicians, Hypatia and Pythagoras, 11-14 years old students can have fun working through a variety of games and print offs.
   http://www.bbc.co.uk/education/mathsfile/

The Metagrobologist  
   Small collection of math puzzles and oddities geared toward gifted 9- to 12-year-olds.
   http://www.geocities.com/themetagrobologist/nav.htm

Mike's Math Club  
   Includes puzzles and games to test knowledge of basic skills.
   http://www.mff.org/mmc

Online Math Games For Kids  
   Has online math games for middle school kids. Worksheets and flashcards too.
   http://www.scweb4free.com

Primary Games  
   A collection of interactive math games.
   http://www.primarygames.co.uk

Dan's Math 4 Kids  
   Gives examples of ways that numbers occur in the world around us. Includes puzzles that concern numbers, geometry, speed rates, and logic.
   http://www.dansmath.com/pages/danskids.html