I have found a few sites that have animated and even interactive animated demonstrations of concepts/principles of physics. I am interested in this topic because there have been many times in presenting new material to students that my static drawings and illustrations just don't get-it. I want them to see the movie I am watching in my own mind. I am interested in all science disciplines, not just physics.
Verizon Thinkfinity has many interactive resources to engage students in learning. Here are just a few for the upper grades:
6-8 Become a Plant Hunter - http://www.nybg.org/planthunters/
6-8 Planet Size comparison - http://www.sciencenetlinks.com/interactives/messenger/psc/PlanetSize.html is a good visual.
6-8 Orbit & Rotation - http://www.sciencenetlinks.com/interactives/messenger/or/OrbitRotation.html
6-8 Fact Challenge - http://www.sciencenetlinks.com/interactives/messenger/fc/FactChallenge.html
6-8 Day on Mercury - http://www.sciencenetlinks.com/interactives/messenger/dom/DayOnMercury.html
6-12 SCI: Skin Cancer Investigation - http://www.sciencenetlinks.com/skindeep/interactive/base.html
9-12 From Cell to DNA - http://www.sciencenetlinks.com/interactives/dna.html
9-12 Protein Synthesis: At the Ribosome: At the http://www.sciencenetlinks.com/interactives/protein.html
3-12 Whatever Happened to Polio: Activities - http://www.americanhistory.si.edu/polio/activities/index.htm
6-12 Backwards Spinning Wheels - http://www.sciencenetlinks.com/interactives/protein.html
Watch for videos to be cataloged into the Search Engine database in the coming months.
Smithsonian's History Explorer has an interesting interactive that allows you to "play" with the actions and reactions of objects. You could also set up the "Tinker Ball" application to demonstrate various effects in class. Check out Invention at Play. http://www.inventionatplay.org/index.html
Here are a three more simulations of real problems that can provide 21st learning skills:
6-12 Power Up - http://www.sciencenetlinks.com/interactives/powerup.html
5-12 Amusement Park Physics - http://www.learner.org/interactives/parkphysics/coaster/
6-8 Evolution interactive - http://www.sciencenetlinks.com/interactives/evolution.html
3-8 Gravity Launch - http://www.sciencenetlinks.com/interactives/gravity.html
9-12 Sound Waves interactive - http://illuminations.nctm.org/ActivityDetail.aspx?id=37