Science Buddies
Science Buddies: Effect of Friction on Objects in Motion
The funny thing about friction is that you couldn't get anywhere without it, yet it still acts to slow you down as you're getting there. Here is an easy project to measure the effects of friction.
Walter Fendt
Walter Fendt: Inclined Plane
This site is an interactive app of an inclined plane showing the effect of the angle, the weight of the block, and the friction as a block is pulled up an incline.