Final answer:
The civil rights movement was a major turning point in black attitudes toward accepting second-class citizenship, as it brought attention to racial discrimination and inequality and led to significant changes in legislation and societal attitudes.
Step-by-step explanation:
The major event that was a turning point in black attitudes toward accepting second-class citizenship was the civil rights movement. The movement brought attention to the racial discrimination and inequality faced by African Americans and galvanized them to fight for their rights. Through protests, marches, and legal challenges, the civil rights movement successfully dismantled de jure segregation and enacted legislation to ban discrimination in various areas, such as housing and education. This movement also led to the rise of black consciousness, with many demanding Black Studies programs that highlighted the history and literature of African Americans.