How the World Works Websites

General Physics
http://www.physics4kids.com/files/motion_intro.html


Magnets

Force and Motion
http://www.ducksters.com/science/laws_of_motion.php

Gravity
http://spaceplace.nasa.gov/what-is-gravity/
http://www.ducksters.com/science/gravity.php

Friction
http://www.ducksters.com/science/friction.php


Simple Machines
http://www.ducksters.com/science/simple_machines.php