The United States decennial census features heavily in the sixth episode of The West Wing (S1E6, "Mr. Willis of Ohio"). In particular, the topic of sampling versus a door-to-door headcount is discussed at length. The episode is 45 minutes long, and would probably be appropriate for high school students and beyond. (Not to say that spending an entire class period on this one episode is the best use of time, but there is certainly value to knowing this episode exists even if it is just for interested students' knowledge.)
While sampling-versus-census is a central focus of the episode, there are other subplots. Some of the subplots may be uncomfortable for some viewers, particularly in the later part of the episode. You should watch the episode before recommending or assigning it and know your audience.