Math Cats    http://www.mathcats.com/cntents.html

Math Links for Kids    http://www.teachingfirst.net/math.htm

Berkeley Kids Click Links    http://sunsite.berkeley.edu/cgi-bin/

PBS CyberChase    http://pbskids.org/cyberchase/parentsteachers/

PBS Zoom (lots of sci)   http://pbskids.org/zoom/

Wendy from LivingMathForum Recommended:

fractions and printable patterns

How one family replaced math textbooks with felt manipulatives and other things

First grade math games

Links to many other pages on symmetry and tesselations

Pythagoras and music and math

This is the same basic story as One Grain of Rice, told a bit differently, but online, with illustrations and hyperlinks.

Pattern blocks to play with online.

Place value activity with zebras- a print out activity.  Click on the words "Zebra Number Stripe" for the graphic this site has other games and activities, too.
Living Math!

Websites and Links - Kid Recommended