Quite important:
The contest is open only to legal residents of the 50 United States, the District of Columbia and Canada (except the Canadian province of Québec) who are at least 18 years old as of the date of entry.
Though in a pinch you could have a North American LWer submit your entry for you and give you credit and eventual prizes, since the rules seem to allow third-party collaboration.
Ars Technica are holding a competition for people to make a science video up to 3 minutes long "to explain a scientific concept in terms that a high school science class would not only understand, but actually be interested in watching". Prizes in three categories: biology, physics, and mathematics. Deadline is December 25. More details here.
Anyone want to have a go at Bayes' theorem? Cognitive bias? Defeating death? Invisible purple dragons?