Books are often banned on the basis of SEX! In 1985 The Chocolate War by Robert Cormier was banned from the Stroudsburg (PA) high school library because… “It’s blatantly graphic, pornographic and wholly unacceptable for a high school library.”
It was also challenged at Beaver Local Board of Education Meeting in Lisbon Ohio in 2001 as a “pornographic book that should be removed from high school English Classes.”
Source: Doyle, Robert P. Banned Books. Chicago: American Library Association, 2001. From the Newsletter on Intellectual Freedom.
Here’s a more recent example:
No Fear Shakespeare Romeo & Juliet, an easy-to-read version of Shakespeare’s Romeo and Juliet produced by Sparknotes, was banned in 2012, because some parents in Liberty, South Carolina were furious that their kids were reading it in middle school. They said it’s too mature for their kids because it discusses sex.
Source: Doyle, Robert P., Books Challenged or Banned 2011-2012 . Chicago: American Library Association, 20011-12. From the Newsletter on Intellectual Freedom.