Mass, Wendy. 2006. Jeremy Fink and the Meaning of Life.
Jeremy is on the verge of his thirteenth birthday when a mysterious package is delivered by the post office. It seems that his father left an engraved box--with four locks--as his birthday present. The only problem? The keys have been lost. There is no way for Jeremy to open his present--this gift of sorts from beyond the grave. But teaming up with his best friend, Lizzy, he’s determined to find the keys that will open the box engraved: Jeremy Fink and the Meaning of Life. Can friendship and determination unlock the keys to the meaning of life in more than one way? Expect lots of humor mixed in with heartfelt moments as two young pre-teens tackle the world.
Consider this I AM THE MESSENGER for kids. (In many ways it really is very similar to Markus Zusak's I Am The Messenger except for the fact that our hero/narrator is much younger.)