It wasn't until about a year or so ago that I started hearing about Dystopian YA Fiction. Dystopian fiction is all about social commentary and how if we don't change how we do things this is how we will end up. They can be futuristic, from the ancient past, apocalyptic, etc. Here are a few of my favorite Dystopian series.
You can read more about Dystopian YA in the New Yorker.
Also here is a list of 50+ Fantastic YA Dystopian Novels.