A Magnetic North or a Magnetic South? We know that like poles repel each other and unlike poles attract each other.
http://my.execpc.com/~rhoadley/magpole.htm
Covers theory, materials, tips on winding inductors and eleltromagnets hints and kinks.
http://www.ee.surrey.ac.uk/Workshop/advice/coils/mu/index.html
In my project I was trying to find out what battery lasts the longest. I will also try to determine if the cost of the battery has anything to do with the power it has.
http://www.freesciencefairproject.com/projects/battery_power.html
Making an electric generator is a good way of learning the principles of generators. It also is an exciting science project.
http://www.scienceproject.com/A/projects/KITWG/index.asp
In this project you will make a set of magnet rings to float above each other while their balance is maintained using a wood dowel. You will then examine the flexibility of the floating rings and propose uses for such a floating set of rings.
http://www.freesciencefairproject.com/projects/simple_magnet_levitation.html
For many years, energy of moving water has been used to grind grains and run machinery such as wood working, knitting and cutting machinery.
http://www.freesciencefairproject.com/physics/water_turbine.html
Wind is a form of solar energy that occurs when the sun heats the air, which causes the air to rise, creating a vacuum.
http://www.freesciencefairproject.com/physics/wind_turbine.html
This clock is citrus-powered
http://pbskids.org/zoom/activities/sci/lemonbattery.html
Electricity: charge it and pass it on!
http://pbskids.org/zoom/activities/sci/lemonbatteryii.html
Create a buzz of your own.
http://pbskids.org/zoom/activities/sci/staticelectricity.html