The Critical Media Project collects curated multimedia content for use in media literacy education in the areas of race and ethnicity, class gender and sexuality. The site hasn't launched yet, but you can see some example of media content and discussion questions here.
It's built using Mezzanine, the same great Django CMS that runs this site. Media artifacts are custom content types. Wistia provides media hosting (for images, sound, and documents in addition to video, which lots of other services don't), and it's integrated via oembed. The site is hosted on Gondor, which made it really easy to deploy new things for review by a distributed team. Good tools make all the difference!