The main problem that the characters in the book "Esperanza Rising" are trying to solve is poverty and the difficult living conditions they face as Mexican immigrants in California during the Great Depression. Esperanza and her family lose their ranch in Mexico due to political turmoil and are forced to immigrate to the United States in search of a better life. However, as immigrants, they experience racism, discrimination, low wages, and exploitation during this economic crisis.
Throughout the story, Esperanza, her mother, abuela, and the other workers strive to overcome these challenges, hoping to find stability and dignity despite the obstacles they encounter in pursuit of their dreams.