Wordia is a free, online video dictionary.
Instead of just simply listing the definition of a word in text, this site goes a step further and includes a video (some professional, some user created) that explains the definition of the word. Some of the videos use music, some use comedy, and some use experts to explain the definition.
Wordia also offers an education section. Wordia Schools provides a private area where students can share videos that they have created. Wordia Schools is free and you can take a tour here to find out more about how the site works.