Several people have asked me how I made those videos in which I walk behind the screen and in front of the screen (See linked videos "April Fools: Math Class Shadow" and "2009 Halloween Math Class"). This video is a "how-to" video that describes the process. Here's the equipment a former student, Andrew Staver, and I used: a Panasonic miniDV camcorder (although the newer models would be better),
{{#tags}}- {{label}}
{{/tags}}