COOL SCIENCE STUFF
Science Fair
Dragonfly
Shout Program
Discovery Education - Many topics to choose from here
Try Science - A fantastic site with many different science ideas 
Children's University of Manchester Science Page
Bizarre Labs - science experiments you could do at home (always check with your parents first)

Marsville - THIS IS THE NATIONAL SITE
Marsville - THIS IS THE LOCAL SITE

Just about electricity
Electricity activities from across the ocean
More from the same place
Frankenstein's Lightning Laboratory
Science Zone
BrainPop Electricity
Power Kids
Explorations for kids
Learning Circuits
Science Electricity Powerpoints
Engineering Interactive - scroll down to the electricity activities