Nelson employs the unusual recurring motif of a series of notes Lennie has written for her sister that she has scattered around the town. Some of them are found and some are not recovered. And they probably won't make sense to anyone who didn't know who wrote them. I had heard from someone who knew the author that she had initially thought of writing the whole book as a series of these notes/poems, but then decided to use them as a motif in a more traditional narrative. I thought this latter approach worked very well, although it would have been interesting to see how it would have worked out if the book comprised only the notes. It would have been more like a "book in poems".
The other motif that resonates through the book is the use of music to express what the characters are feeling, as several of the main characters are musicians. While this is a familiar motif, it is also used here to great effect. There's also a floral motif which is pretty cool as well. This is a very strong debut novel that will appeal to those who like teen romance as well as those who want something a little deeper. I'm interested to see what Nelson does next.