A great introduction to simple machines! Try some of the activities at home! http://www.mikids.com/Smachines.htm
http://www.cdli.ca/CITE/machinessimple.htm
GREAT science interactive resources! Especially good is the Simple Machines activity! http://www.edheads.org/activities/simple-machines/index.htm
Interactive science and engineering activities for ages 9-11 http://www.engineeringinteract.org/
Learn about 6 types of simple machines. http://teacher.scholastic.com/dirtrep/simple/index.htm
Definitions of 6 types of simple machines from the Franklin Institute. http://www.fi.edu/qa97/spotlight3/spotlight3.html