The Mystery of the Love List by Sarah Glenn Marsh
Pippa’s teacher tells her students to make a love list–a list of all the things that take up room in their hearts. Pippa makes her list, but when she finds someone else’s and sees that her own name has been written down, along with all of her favorite things, she discovers she has a secret admirer! Maybe the best friend she’s always hoped for is right in her classroom, if only she can crack the case. Good thing there’s nothing Pippa loves more than a good detective story. Will she solve the mystery of the love list and find a new friend?