Since You've Been Gone by Morgan Matson (Contemporary Fiction)

Since You’ve Been Gone    By Morgan Matson

What do you do when your best friend disappears…right before what was supposed to be the best summer of your life? Emily goes on a quick vacation with her family and upon her return sends message after message to her friend, Sloane. Only to realize Sloane isn’t answering. Right before she is going to tell her parents that her best has disappeared, Emily receives a letter in the mail from Sloane. It is much like other lists that Sloane has sent her over the last two years they’ve been friends. Emily becomes convinced if she does the things on the list, she’ll figure out what has happened to her friend. 

Recommended for grades 8 and up.