Bilal and his sister Ayesha have recently moved from Chicago (where there were lots of other Muslim kids) to this unspecified location where they seem to be the only Muslim kids. Some boys tug at Ayesha's headscarf and laugh at her. One of these boys turns out to be in Bilal's class, and Bilal decides to pretend his name is "Bill" (thus hiding his Muslim identity).
The teacher is a Muslim and a friend of Bilal's father and keeps him after class to talk to him (in a scene which is a two-page spread of text, which seems a bad choice for a picturebook) and agrees to keep his secret but also asks if Bilal would be willing to read a book for him. He brings the book to evening prayers that night to give to Bilal and it turns out to be titled Bilal Ibn Rabah: Friend and Helper of the Prophet -- about someone from the beginning of Islam who was persecuted for being a Muslim. (The teacher tells Bilal that, "Bilal and the early Muslims knew it was more important to please God than to please the people.")
It feels a little weird to me that Bilal's parents never told him about his namesake, but Bilal's reading of the book predictably inspires him. The next day, he intervenes when Ayesha is bullied again (and comes out as Muslim and his real name), and apologizes to Ayesha for not standing up for her the previous day. "It's okay. I'm glad you were on my side today."
After school that day, Bilal plays basketball with some other kids at a nearby park. While playing, he sees the bully standing by the fence, frowning, and after the game is over, he goes over and invites the bully to play -- on his own team, no less. This feels a bit much -- especially the fact that the bully not only accepts but adjusts to being basically nice to Bilal.
A bit I did like is that a kid says he needs to stop playing and will be back in a few minutes, and when Bilal asks a teammate where he had gone, the teammate says, "He's Muslim. He always prays in the afternoon." Bilal is surprised that this isn't a problem for this other kid, but the teammate says no, he doesn't mind; "It gives me more time to practice." So Bilal then chases after the Muslim kid, and they pray together. Bilal even gives the call to prayer -- an echo of how his namesake was the first person to give the Muslim call to prayer.