The idea for this post came from The Horn Book's recent blog post on Hunger Games-ish books for young children. Admittedly, it's a small group, since the darker themes of dystopia/post apocalypse don't lend themselves well to young children's literature, but there are several possibilities:
Book of Ember series
The Boy at the End of the World (mentioned in the blog post)
Eager (mentioned in the blog post)
The Roar series
The Tripods trilogy
In other news, I blogged about color-themed books on the ALSC blog--and author/illustrator Ashley Wolff, creator of the gorgeous Baby Bear Sees Blue, commented on my post (be sure to check out the video link that she shares)!