White House for Kids http://www.whitehouse.gov/kids/whlife/index.html
National Geographic for Kids http://www.nationalgeographic.com/kids/
A great site for learning more about fractions. http://visualfractions.com/
You can use this as a timer. http://online-stopwatch.com/
This is a great site for all kinds of math practice. http://www.ixl.com/
Kid's Place - Houghton Mifflin Math http://www.eduplace.com/kids/mw/
Great web site with lots of options. http://www.coolmath4kids.com
Best web site ever for practicing map skills. http://www.sheppardsoftware.com/