Look, anything Andrew Clements writes is good, but Things Hoped For stands out in my mind for several reasons.
First, it is an extremely engaging story. Gwen is in New York City to prepare to audition to study violin at some of the top violin schools. She is staying with her beloved (but fairly solitary) grandfather. Soon after arriving, she comes home to find a phone message from her grandfather, saying he will be gone for a while and that she should just carry on as it he is still around. She does her best to focus on her auditions, even though her grand-uncle keeps visiting and making threats about selling the apartment, even though she has met a guy named Robert who is also in town to audition (in this case for trumpet) and even though they encounter a very mysterious and threatening figure. And from that point, the book really picks up speed.
Second, Clements is really good at balancing all sorts of tension. As a reader I found myself often concerned for Gwen, but never to the point of desperation. Some scenes were frightening, but not too frightening. And the romantic tension between Gwen and Robert was perfect -- without resorting to old standbys of them suddenly hating each other/breaking up, or taking the relationship too far physically and having to deal with that. This is just a real love story about two kids.
Third, the ending was satisfying.
Fourth, although there are some huge connections between this book and the previous one in the series Things not Seen, it is not necessary to read either book to understand and enjoy the other.
And finally, Clements is really good worth words. He paints beautiful pictures in your head.
Although the main character is a girl, I am guessing that confident male readers would like this one a lot too. It is probably best for really strong fifth grade readers through high school or beyond. I cannot imagine anyone challenging this book for any reason (though I have been surprised before). It is a good one. Go buy it!