Santa's Dirty Socks

CS Unplugged is a series of activities designed to teach computer science without a computer.  I've used them many times for outreach activities and even in an undergraduate course I taught.  The creators have been uploading some great videos relating to computer science topics, and I wanted to share this one:

This original story introduces the idea of a divide-and-conquer algorithm using a narrated picture-book verse about the serious problem of finding a pair of dirty socks that have been accidentally wrapped with a child's present. The idea is that this can be played or read to students, and then can be used as the basis for a follow-up discussion. A set of discussion starter questions is available (http://csunplugged.org/divideAndConquer­) to encourage students to engage in computational thinking and think about algorithm analysis in the story 1024 presents are searched in 10 steps, and students can be asked to extend this to other cases, and generally think about the implications of having an algorithm with logarithmic complexity.

 Check out all the videos.