Based on that classic question - if a bird flies in a box, how much will it weigh? I believe mythbusters did a larger scale demo of this, but this video is a no-frills version that shows the process clearly. Now if only I could use some dry ice smoke or something to visualize the air flow in the box...
And, yes, you can easily use this in your physics class - this mini quadcopter drone cost just US$20+, even cheaper if you order directly from the manufacturers.
