Sylvia is a third-grade Mexican/Puerto Rican American girl whose family recently moved to a farm in Westminster, California. Proud of her heritage, she becomes aware of discrimination when the local school refuses to admit her due to her skin color and Latina surname. She is observant, empathetic, and deeply respectful of her father's fight for educational equality.

Aki is a third-grade Japanese American girl whose ordinary life on her family's asparagus farm ends abruptly following the onset of World War II. Forcibly relocated to the Poston incarceration camp in Arizona, she struggles with the harsh living conditions and the traumatic separation from her family members. She clings to the hope of returning to her California home.

Gonzalo is Sylvia's father, a naturalized US citizen from Mexico and a hardworking farmer. Passionate about justice, he refuses to accept the discriminatory practices that force his children into a second-class school. He organizes petitions and ultimately pursues a legal battle to ensure equal educational opportunities for all Latinx children.

Seiko is Aki's much older brother and an American citizen by birth who legally owns the Munemitsu family farm. Following his father's sudden arrest, Seiko assumes the role of the family's head at the Poston incarceration camp. He wrestles with the government's hypocritical loyalty questionnaires as a young man trying to survive an unjust system.

Felicitas is Sylvia's mother, a Puerto Rican American woman who supports her husband's legal battle against school segregation. She effectively runs the family farm while Gonzalo focuses on the lawsuit. She believes firmly that every child deserves a fair chance at a quality education.

Seima is Aki's father, an Issei (first-generation Japanese immigrant) who is legally barred from owning land or gaining US citizenship. He is suddenly taken away and held in a separate Department of Justice detention facility, causing great distress to his family.

Masako is Aki's mother, who strives to hold her family together through the trauma of forced incarceration. She faces immense emotional strain and provides quiet counsel to her children during their internment.

David Marcus is a civil rights lawyer hired by Gonzalo Mendez. He takes the school desegregation case to federal court, arguing that separating students based on their ethnic background violates the equal protection clause of the Constitution.

James L. Kent is the superintendent of an Orange County school district who defends the segregation of Latinx students. During his court testimony, he makes false and discriminatory claims regarding the hygiene and academic abilities of the Latinx community.

Mr. Monroe is the local banker who assists the Munemitsu family by arranging for the Mendez family to lease their farm. His intervention ensures the Munemitsus retain ownership of their property rather than losing it during their incarceration.

Mr. Rivera is a local florist who connects Gonzalo Mendez with civil rights lawyer David Marcus, setting the integration lawsuit in motion.

Soledad is Gonzalo Mendez's sister. She becomes furious when the school accepts her lighter-skinned children but rejects Sylvia and her brothers, prompting her to walk out and report the incident to Gonzalo.

Gonzalo Jr. is Sylvia's brother who is barred from attending Westminster School due to his darker skin tone, forcing him to attend the dilapidated Hoover School.

Jerome is Sylvia's brother who shares the experience of being denied entry to the local school and being sent to the segregated facility.

Saylo is Aki's brother who experiences the forced relocation to the incarceration camps along with his mother, sister, and older brother.