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NASA

Nasa: Beginner's Guide to Aerodynamics

For Students 9th - 10th
Includes exhaustive information and a wealth of activities pertaining to aerodynamics and the physics of flight.
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Other

Personal: The Laws of Motion

For Students 9th - 10th
This personal site explains the physics of angular momentum and their application to flight. Part of a much larger site on the procedures, principles, and perceptions of flight.