Hi Marc,
Thanks for viewing our video and your comments. yes the tennis racket theorem is one of our favorite examples since one sets up the problem using the Euler equations (essentially the equations of motion for the rotations of a solid body) and then out of the mathematical analysis of these equations comes some very simple result that can be easily seen with any object having 3 distinct moments of inertia. The Wikipedia page for this
(http://en.wikipedia.org/wiki/Tennis_racket_theorem)
gives the basic set up but as mentioned the explanation would only make sense to someone who already knows what all the parameters mean. But given that this is the case one can then see why the long and short axis give stable wobbling around these axes and why the intermediate axis gives tumbling.
Also one warning if you use this for students the white board picture of the Explorer 1 could lead to the wrong impression that the direction of the angular changes since for artistic proposes we kept the orientation of the Explorer one the same. The animation of the Explorer 1 gives a more accurate representation of what happened -- the angular momentum (both magnitude and direction) remained the same while the Explorer 1 changed its orientation.
We will have a look at your videos and send comments as well. We had also thought to make a longer 3 segment version of our story but were working against the August 12th deadline which got extended to August 22nd.
Best regard and luck with the contest,
Mike, Max, Simon, Dan, Doug