Deza is a highly intelligent, twelve-year-old girl living in Gary, Indiana, during the Great Depression. She loves reading, values her education, and takes enormous pride in her academic performance. Despite suffering from severe cavities, she maintains an optimistic outlook and deeply cherishes her tight-knit family.

Roscoe is Deza's father, an unemployed but determined man born in Flint, Michigan. He uses humor, poetry, and alliteration to teach his children about the real world and keep their spirits high. He desperately wants to provide a stable life for his family but struggles to find consistent work during the economic downturn.

Margaret is a practical and resilient woman who works cleaning houses for wealthy families in Gary. She takes on the heavy burden of providing for the family during her husband's unemployment. She holds strong moral expectations for her children and tries to steer them away from unsavory influences.

Jimmie is Deza's fifteen-year-old brother. He is physically small for his age but makes up for it with a loud, confident swagger and a willingness to fight. He possesses an exceptionally beautiful singing voice and often tries to solve the family's problems, though his methods sometimes involve petty theft or associating with shady characters.

Mrs. Needham is a dedicated, soon-to-retire sixth-grade teacher in Gary. She views Deza as a once-in-a-career student and takes a special interest in securing her future. She provides Deza with advanced tutoring opportunities and new clothing to boost her confidence.

Clarice is Deza's best friend and constant companion during the summer months. She frequently accompanies Deza to the public library and local baseball games, providing emotional support through childhood challenges.

Dolly is a poorly performing student in Deza's class who often resorts to bullying. He targets Jimmie physically in the neighborhood and attempts to intimidate Deza.

Dr. Bracy is an educated, well-spoken woman living in Gary. Rather than calling the authorities when Jimmie steals from her, she creates a strict punishment involving yard work and writing tutoring to teach him a lesson.

Mrs. Ashton is a white librarian who oversees the local public library. She makes condescending remarks about race while believing she is offering compliments to her patrons.

Mr. Henderson is a former steel mill worker who earned his nickname because he can withstand extreme heat inside the furnaces. He is a friend of Roscoe Malone who invites him on a fateful fishing trip to Lake Michigan.

Mrs. Carsdale is Margaret Malone's employer in Gary. She holds deep prejudices against Black workers and fails to appreciate Margaret's dedication and hard work, keeping a very cold distance from her employee's struggles.

Marvelous Marvin is a local "numbers man" who runs gambling schemes. He offers the Malone family temporary help and transportation, flashing his wealth in a way that worries Margaret but impresses her son.

Miss Carter is a seasoned traveler who provides the Malone family with crucial survival advice. She teaches them the harsh realities and practical methods of safely "riding the rails" in boxcars.

Known primarily as "Stew," Donna is a resident and unofficial leader of a homeless encampment in Flint. She maintains order by enforcing cleanliness rules and helping newcomers settle into the community.

Zeke, known as Saw-Bone Zee, is a traveling white musician who recognizes Jimmie's exceptional singing talent while passing time in the camp.

Mr. Alums is a teacher who recognizes Deza's thirst for reading. He gifts her books that feature respectful, authentic portrayals of Black characters, greatly inspiring her intellectual growth.

Mrs. James is a kind postal worker who watches Deza check for mail every day. She shares in Deza's excitement when correspondence finally arrives for the family.

Dr. Mitwally is a dentist who treats Deza's severely decayed teeth, providing her with her first true relief from dental pain in years.