Via the TechLEARNING blog, here's an online media literacy quiz from PBS: http://www.pbs.org/teachers/media_lit/quiz.html
Here's a sample question: What percentage of Americans under the age of 30 read a newspaper on a typical day?
Wow! I thought I was pretty savvy, but I only got 4 questions right! Even better, after you take the quiz, you'll see an explanation for each answer and the source for all of the data cited. There are even links to related websites and classroom activity ideas. If nothing else you'll be able to start some great discussions, especially after you survey your own students.