How does Brent change over the course of the book Whirligig by Paul Fleischman?

At the
beginning of the book, Brent is a selfish, listless, and angry teenager. Once he is traveling on
his own and has an assignment to do €“ to build four whirligigs in Leas honor, in the four
corners of the country €“ he finally has a purpose and a set of goals to work...