The audition date was set. On Dec. 4, students at Alexander Hamilton High School in Elmsford, N.Y., would have the chance to flaunt their vocal chops with the hopes of landing a role in the drama club’s highly anticipated spring musical: Disney’s “Tarzan.” But just days before the scheduled tryouts, administrators announced a change of plans. Instead of “Tarzan,” the Westchester County high school would be putting on a musical adaptation of William Shakespeare’s “Twelfth Night.” The reason for the abrupt change? Two parents complained about racism. “The concerns were over the original story line behind ‘Tarzan of the Apes,’...