Unlock Art is a series of videos from the Tate museum in London; they cover a wide range of topics like Surrealism, Women Artists, Nudes, and the Art Market. These videos would be better for a more mature high school or Art History class due to the mature content of some of the artworks featured in the videos. Nothing out of the ordinary for the art world but view them before showing them in your classroom if you have sensitive classroom or district.
Here are few of my favorites from the series:
You can view all of the Unlock Art series, along with other videos from the museum, on their YouTube channel: https://www.youtube.com/user/tate