http://www.multiplication.com/interactive_games.htm -
Multiplication games.

http://www.netrover.com/~kingskid/Math/math.htm and
http://www.sheppardsoftware.com/math.htm - Fun math games to
practice basic arithmetic.

http://www.tutpup.com/ - On this site students can play games
against other students.

http://www.ixl.com/
- Geared for grades K-6.

http://www.prongo.com/games/ - Multiply games including games to
review multiplication by 10, 100, etc.

http://www.thekidzpage.com/learninggames/index.htm - Includes
games to practice decimals.

http://www.gamequarium.org/dir/Gamequarium/Math/ - Games for
K-12.

http://www.theproblemsite.com/ - This site contains some unique
games that challenge students to consider sequences of numbers.

http://www.ictgames.com/resources.html - This site has early
numeracy games by James Barrett, including topics for ordering,
counting, time, bridging through ten, comparing, addition,
subtraction, place value, multiplication, division, doubles, and
more.

http://www.mathplayground.com/games.html - For elementary and
middle school students.
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