At one point during the movie, Denzel's character inspires his students with lines from "I, Too, Sing America," a poem by African-American poet Langston Hughes. "It was just great to get the opportunity to recite poetry on film [and] to bring up the names of these greats [like] Langston Hughes and Countee Cullen," he says.
In another scene, co-star Forest Whitaker tells the young actor playing his son, "We do what we have to do so we can do what we want to do."
This line, Denzel says, is something he and his wife have been saying to their four children, John David, Katia, Olivia and Malcolm, for years. "That was just something I threw in the film, and it worked well," he says.