Seems to me metadata just means "greater information related to a specific thing" – like categories a blog post would fall under, for example. Or information about who authored a document, the last time it was modified, the program used to create it, etc.
Yeah, schools aren't the greatest for web developers. I think you can learn a lot more by just RSSing a few good websites and reading them religiously (and pick up a few good books too).
And I'm not even in college yet! Jeezus.