Content Knowledge

Information on simple machines can be found at:
http://atlantis.coe.uh.edu/archive/science/science_lessons/scienceles1/finalhome.htm

http://www.fi.edu/qa97/spotlight3/

Information on the engineering design process can be found at:
http://www.nasa.gov/audience/foreducators/plantgrowth/reference/Eng_Design_5-12.html

Numerous websites can be found on catapults.

Information on potential and kinetic energy can be found at:
http://science.howstuffworks.com/engineering/structural/roller-coaster3.htm