http://www.cosi.org/onlineExhibits/simpMach/sm1.html
http://www.brainpop.com/tech/simplemachines/
http://www.edheads.org/activities/simple-machines/sm-glossary.htm
http://www.fi.edu/qa97/spotlight3/spotlight3.html
http://teacher.scholastic.com/dirtrep/simple/
http://edtech.kennesaw.edu/web/simmach.html
http://207.10.97.102/elscizone/lessons/land/simplmachines/default.htm
http://www.henry.k12.ga.us/cur/simp-mach/default.htm
http://www.mikids.com/Smachines.htm
http://www.sirinet.net/~jgjohnso/simple.html
http://science.howstuffworks.com/pulley.htm
http://www.mos.org/sln/Leonardo/InventorsToolbox.html