Spinelli creates a deliberately humorous picture of two people who are unhappy in their marriage but do not want to separate due to religion by describing how they split all their possessions and refuse to speak.
Discrimination against Jeffery
Some would believe it ironic that Jeffery experienced discrimination (including bullying and graffiti) due to his skin color. However, in truth it is reasonable the black people of East End had stereotypes and prejudices about white people just as the inhabitants of West End would have stereotypes and prejudices about black people. Spinelli likely drew out this irony or parallel to demonstrate that all people hold stereotypes and that they can be harmful in either direction.
There are two parts to the irony of Earl Grayson's education. First, Grayson's teachers and school did not believe in his academic capabilities (nor those of his classmates who were likewise poor or had bad parents) and this directly led to his not achieving. Furthermore, Grayson very late in life defies those expectations by taking great joy in reading.
Jeffery as a Father
Jeffery is made to act as a father to Piper and Russell because of their lack of a true father figure. Yet, he has even less of a father, having lost his in a trolley accident.
Maniac Magee Questions and Answers
The Question and Answer section for Maniac Magee is a great
resource to ask questions, find answers, and discuss the novel.
The Lost Year happens after Maniac runs away from his Aunt Dot and Uncle Dan. We really know nothing about what happens during that year up until he shows up in Two Mills. Your speculation would be as good as mine.