Daughter of the Forest - Juliet Marillier I first read this book in middle school when I got Son of The Shadows as a gift and then read them all out of order. This first in the series is a great set up for the series because it crosses farther into the realm of fantasy than subsequent novels. The magical realism takes you into a different time and place (England and Ireland in the late 830s to early 840s, if you're going by mention of King Ethelwulf of Wessex) when otherworldly things might happen and were taken for granted and chalked up to fairy mischief.
If this one doesn't impress you, keep reading anyway because Son of The Shadows is the best in the series, in my opinion, and you get to see many of the young characters in the middle of their lives as the people they've turned out to be.