A novel that is banned in one district might not end up being used for a literature excerpt on a standardized test in a district where that book is allowed. This cause and effect relationship between book bans and the tests students take is one fallout of the Common Core, according to a recent Economist article.

In the past, when a book was banned in one school library, district or state--there would be no effect on students in other parts of the country. Acceptable standards for literature vary widely from region to region. Toni Morrison’s The Bluest Eye is on the list of recommended books in the Common Core standards, yet after a parent in North Carolina complained about the “inappropriate” book, the passage was removed from standardized tests, according to the article.

Not only is the novel a tremendous literary achievement by a Nobel and Pulitzer prizewinning author, it is also a hallmark text for understanding America’s history of racial and social injustice. But some see its inclusion in the Core curriculum as reason enough to reject the standards. At legislative hearings in North Carolina, the book was compared to “Fifty Shades of Grey” and condemned for promoting pornography.

Throughout the country lessons on climate change, evolution, figures in history and math methods are often questioned informally by Common Core critics. Formal challenges to the Common Core content may increase—in fact, four states have completely opted out of the standards. The consistent standards were created to improve the minimum level of performance for American students. However, authoritative school districts have existed for decades answering only to themselves when it comes to items as specific as whether to select or ban a book for study.