Esperanza Rising by Pam Muñoz Ryan

Esperanza thought she'd always live with her family on their ranch in Mexico--she'd always have fancy dresses, a beautiful home, and servants. But a sudden tragedy forces Esperanza and Mama to flee to California during the Great Depression, and to settle in a camp for Mexican farm workers. Esperanza isn't ready for the hard labor, financial struggles, or lack of acceptance she now faces. When their new life is threatened, Esperanza must find a way to rise above her difficult circumstances--Mama's life, and her own, depend on it.