to interested students with parental consent. Such decisions have been criticised: the American Civil Liberties Union noted the importance of engaging with the novel's themes in places where racial injustice persists. Becky Little, of The History Channel, and representatives of the Mark Twain House noted that the value of classics lies in their power to "challenge the way we think about things" (Twain's Adventures of Huckleberry Finn has attracted similar controversy). Arne Duncan, who served as Secretary of Education under President Obama, noted that removal of the book from reading lists was evidence of a nation with "real problems". In 1966, a parent in Hanover, Virginia, protested that the use of rape as a plot device was immoral. Johnson cites examples of letters to local newspapers, which ranged from amusement to fury; those letters expressing the most outrage, however, complained about Mayella Ewell's attraction to Tom Robinson over the depictions of rape. Upon learning the school administrators were holding hearings to decide the book's appropriateness for the classroom, Harper Lee sent $10 to The Richmond News Leader suggesting it be used toward the enrollment of "the Hanover County School Board in any first grade of its choice". The National Education Association in 1968 placed the novel second on a list of books receiving the most complaints from private organizations—after Little Black Sambo. With a shift of attitudes about race in the 1970s, To Kill a Mockingbird faced challenges of a different sort: the treatment of racism in Maycomb was not condemned harshly enough. This has led to disparate perceptions that the novel has a generally positive impact on race relations for white readers, but a more ambiguous reception by black readers. In one high-profile case outside the U.S., school districts in the Canadian provinces of New Brunswick and Nova Scotia attempted to have the book removed from standard teaching curricula in the 1990s, stating: Furthermore, despite the novel's thematic focus on racial injustice, its black characters are not fully examined. In its use of racial epithets, stereotyped depictions of superstitious blacks, and Calpurnia, who to some critics is an updated version of the "contented slave" motif and to others simply unexplored, the book is viewed as marginalizing black characters. One writer asserts that the use of Scout's narration serves as a convenient mechanism for readers to be innocent and detached from the racial conflict. Scout's voice "functions as the not-me