Interesting Web sites for teaching math...
The Maths Apprentice
http://www.mathapprentice.com/Activity/explore.html
This is a primary and middle school site for mathematics directed at the younger audience.
Kids Online: Me and Mymaths
http://www.kidsolr.com/math/math.html
This is a primary and middle school site, but a useful math site.
Dan’s Maths
http://www.dansmath.com/
This site is directed at the more senior school audience but is still applicable to middle school students.
MathAtube
http://www.mathatube.com/
Video tutorials and resources for mathematics
US Government Data
http://www.data.gov/
This is a great source of accurate information and statistics. Applicable to mathematics, humanities and many other subject areas.