Throughout the novel, Merci struggles with her socioeconomic status at Seaward Pines. As a scholarship student, she must complete 60 hours of unpaid labor for the school every year. She cannot spend money as lavishly as her peers do—even on mundane things, such as school portraits. Her father reminds her that she must be more virtuous and forgiving than her peers because they pay their tuition, and she does not. At numerous times throughout the narrative, Merci fibs to her classmates to compensate for the stigmatization she feels as a person from a lower socioeconomic class, or to cover her ignorance to the things that those in higher socioeconomic classes take for granted. Through this dynamic, Medina paints a portrait of the ways that America’s class-stratified society impacts a child’s life in both every day and intimate ways. Through her treatment of the complexities of Merci’s experiences, Medina paints a detailed portrait of the social and psychological impact of class oppression. 

A major plot device in Merci Suárez Changes Gears is Lolo’s decision to keep Merci in the dark about his Alzheimer’s diagnosis. As a result of Lolo’s wishes, the entire family keeps the reality of Lolo’s disease a secret from Merci.