Why is the information of the Beale family shocking to Grayson in maniac Magee?

In "Maniac Magee," Grayson is shocked to learn about the Beale family's situation because it starkly contrasts with his own experiences and perceptions of community. He discovers that the Beales, an African American family, face racial discrimination and economic challenges, which highlights societal injustices that Grayson had been largely unaware of. This revelation deepens his understanding of the complexities of race relations and the struggles faced by those in his community, prompting him to reflect on his own beliefs and biases.