First and foremost,
Bomb: The Race to Build—and Steal—the World's Most Dangerous Weapon by Steve Sheinkin. Mary's started this and loves it. It's non-fiction, espionage. Try it with your older kids.
No Crystal Stair by Vaunda Micheaux Nelson. Part non-fiction, part fiction. Unusual. Worth examining.
Wonder by R.J. Palacio. Huge buzz on this book.
Summer of the Gypsy Moths by Sara Pennypacker. I've met Sara Pennypacker. She is lovely, and I love her Clementine book. This is a really unusual book, and funny. Definitely try it.
The One and Only Ivan by Katherine Applegate. Calvin loved this book. It's from the perspective of the gorilla. If you have an animal lover of any kind, give them this book!
Liar and Spy by Rebecca Stead. Interesting. A mystery. Not as good, in my opinion, as When You Reach Me (former Newbery winner) but worth trying if you loved When You Reach Me.
Splendors and Glooms by Laura Amy Schlitz. So unusual. This woman is an incredible writer. It's a bit of a beast (lots of pages!), but worth the journey.