Almost all of math presented and explained with a chalkboard and a friendly voice in ten-minute YouTube videos
: http://www.khanacademy.org/

The associated exercises for this website are at this link:
http://www.khanacademy.org/exercisedashboard

Explanations, practice problems, and quizzes:
http://www.purplemath.com/modules/index.htm

Explanations, practice problems, and quizzes:

http://www.sosmath.com/index.html

http://library.thinkquest.org/20991/geo/

Explanations, practice problems, and quizzes:

http://www.mathpower.com/

http://www.onlinemathlearning.com/

Explanations and help with your specific math problems:
http://www.webmath.com/

Practice quizzes and games:
http://www.thatquiz.org/

Explanations and help with your specific math problems:

http://www.algebrahelp.com/

Links to math resources:
http://www.purplemath.com/

Conjectures in geometry:
http://www.geom.uiuc.edu/~dwiggins/mainpage.html

GED practice tests:
http://www.learnatest.com/LEL/index.cfm/

Conversions calculators:
http://www.metric-conversions.org/

Graphing calculator:
http://www.coolmath.com/graphit/

Math tutoring:
http://www.mathtoearth.org/

Websites for math anxiety:
http://www.mathacademy.com/pr/minitext/anxiety/index.asp

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