Amusement Park Physics:
http://www.learner.org/interactives/parkphysics/coaster.html
http://www.learner.org/interactives/parkphysics/parkphysics.html
The Physics Classroom:
Glencoe:
http://www.glencoe.com/sec/science/cgi-bin/splitwindow.cgi?
top=http://www.glencoe.com/sec/science/top2.html&link=
http://library.thinkquest.org/2745/data/ke.htm