Joe is the other protagonist of the novel. He is a large fifth grader who struggles with Auditory Processing Disorder (APD), making it difficult for him to focus on spoken words. Joe is often bullied, particularly by Dillon, and experiences anxiety related to school. Despite these challenges, Joe is easy-going and forgiving, aside from his interactions with Dillon. His relationship with his teachers, especially Mr. Barnes and Miss Frost, plays a significant role in his development. Joe learns to stand up for himself and forms a friendship with Ravi.

Dillon is the most popular boy in fifth grade and serves as the antagonist of the novel. He is initially seen by Ravi as someone who might become a friend but turns out to be a bully. Dillon embodies the traits opposite to Joe and acts as a cultural foil to Ravi, highlighting the differences in their backgrounds. His need to humiliate others and his greed contrast sharply with both Ravi and Joe's characters.

Mrs. Beam is Ravi and Joe’s fifth-grade teacher. She is characterized by her expressive eyebrows and serves as a source of conflict for both boys initially, as she misunderstands them. Mrs. Beam unintentionally causes anxiety for Joe by calling on him during class and repeatedly mispronounces Ravi’s name. Over time, Mrs. Beam attempts to understand and support both boys.

Miss Frost is the resource room teacher at Albert Einstein school. She helps Joe with exercises to manage his APD and serves as a source of understanding for him. For Ravi, Miss Frost represents a voice of reason, guiding him toward empathy. Her individual attention to students is contrasted with Mrs. Beam's approach, highlighting the benefits of one-on-one engagement.

Mr. Barnes is Joe’s former fourth-grade teacher and serves as a mentor to him. Joe looks up to Mr. Barnes, who was accommodating regarding Joe’s APD and shares similar interests with him, such as a love for patterns. Mr. Barnes provides advice and support, which Joe internalizes as a guiding voice throughout the novel.