Aside from Maniac Magee, the only Spinelli book I've ever read is Stargirl, which might be one of my favorite young adult novels that I randomly happened upon in my youth. I didn't really like Maniac Magee as much, but I definitely see why it's a beloved book of many, including one of my students who walked by as I was reading it and started gushing about how much she loved the book.
Like Stargirl, Maniac Magee features a main character who changes a town with his eccentricities. The town is in awe of his legendary status (one-handedly catching and kicking a football, bunting a frog for a home run, etc.), placing him on a metaphorical pedestal, until it comes crashing down thanks to the town's racial divisiveness.
Magee is blind to race, much like Stephen Colbert. His interactions between the black East Enders and the white West Enders results in strife for those residents who are against mixing and don't understand how the other side lives. It's an interesting examination of racial struggle as seen through the life of this bizarre boy legend.
The book also examines homelessness, as the orphan Magee comes to the town after running away (literally) from his aunt and uncle, and struggles to find a permanent place to live. It contributes to the racial themes of the book, posing the question of belongingness.
I enjoyed the first two parts of the novel, but the third part seemed a little forced to me. I still enjoyed the book as a whole, and there's no question why so many elementary school teachers feature this novel in their lessons each year.