(CNN)Two students have sued a Missouri school district over its decision to remove eight books from school libraries, arguing the novels were banned because they discuss issues surrounding race, gender and sexual identity.

The lawsuit was filed Tuesday by the American Civil Liberties Union of Missouri (ACLU) against the Wentzville School District on behalf of the students who are minors and not named in the complaint.

"The banned books engage their readers with a diversity of ideas and minority viewpoints, including with respect to race, gender, and sexual identity," the ACLU argues in the class action lawsuit.