When I taught English at high schools in Canada, I was a regular at the local library borrowing interesting new short films created by the National Film Board.
YouTube was a wonderful addition to my ability to find visual examples of complex ideas, interviews and performances both historical and current, and so much more. However, YouTube is blocked in so many schools that I have to teach my education students how to download the videos for themselves so they could use them inside the school walls.
That barrier seems to be breaking down or, at least, a new announcement from YouTube will help. YouTube for Teachers is now available and just a little way in you will discover ways to use the service efficiently in your classroom. The creation of playlists, quizzes, video quests, and more are just a few things teachers new to the site will learn. I think, in time, districts will begin to reduce their restrictions on YouTube in the classroom. In the meantime, I would urge you to become a member of YouTube Teachers to keep engaged with the discussion.