Mechanics

Skateboard Science - The techniques and equipment skateboarders use to seemingly bend the law of gravity. In the trickscience section, the site explains the physics behind the stunts, and several experiments to try at home. The equipment section offers an in-depth look at skateboard design.
http://www.exploratorium.edu/skateboarding/index.html

The K-8 Aeronautics Internet Textbook - Resources for those interested in aeronautics including an online textbook, sign language dictionary, explanations of the principles of aeronautics, lesson plans, interactive activities, and curriculum bridges to other subjects.
http://wings.avkids.com/

How Stuff Works: Force, Power, Torque and Energy - Animations for explaining the concepts of force, power, torque, and energy.
http://www.howstuffworks.com/fpte.htm

Computer Physics on the Playground - A physics curriculum for upper elmentary and middle school designed to relate the experience children have on the playground to basic physics concepts.
http://home.hockaday.org/HockadayNet/Academic/physics/playground/playground.htm

Motion and Force - Various aspects of mechanics are explored allowing the user to change variables to learn the concepts
http://www.explorelearning.com/index.cfm?method=cResource.dspResourcesForCourse&CourseID=330

SLIK - Tutorial on kinematics targeting undergraduate engineering students taking courses such as engineering mechanics. Common textbook kinematics problems are solved - always using the same method of solution - the SLIK method. SLIK stands for "Simple Loop Interpretations for Kinematics."
http://home.nycap.rr.com/slik/slikd/index.html

Amusement Park Physics - Explores how the laws of physics play a role in the design of amusement park rides. Activities invite visitors to design a roller coaster and determine the outcomes of bumper car collisions. Links to related sites are provided.
http://www.learner.org/interactives/parkphysics/index.html

Physics on the Playground - Playgrounds are a place to observe physical forces, such as gravity, momentum, and friction. This set of exercises invites students outdoors to take a closer look.
http://content.scholastic.com/browse/article.jsp?id=3615

Matter and Materials - Fluid Mechanics - A lesson outline on the topic of fluids. Looks at topics such as viscosity, buoyancy, density, volume and how hydraulics and pneumatics plays an important role.
http://camillasenior3.homestead.com/fluids.html

The Hydrodynamic Propulsion Rocket - Water-propulsion rocket and launch pad described, analyzed and explained and then tested.
http://fanciulli.liceipoliziani.com/HydroRocket/Home_pg_HydroRocket.htm

Teaching Dynamics with Excel97 - The material presented here is designed to be directly useful to a teacher or student in a more traditional high school or beginning university physics course on mechanics. There are profuse instructions, and some prewritten spreadsheets are available as well.
http://galileo.phys.virginia.edu/classes/581/

Longitudinal and Transverse Wave Motion - Explanations with animations.
http://www.gmi.edu/~drussell/Demos/waves/wavemotion.html