Story highlights A library group says books featuring diverse characters are increasingly targeted for bans

Three of the 10 most-challenged books are graphic novels

(CNN) Upwards of 11,300 books have been challenged since 1982 for content that some consider to be offensive, according to the American Library Association.

During Banned Books Week , celebrated this year from September 27 to October 3, book lovers unite to fight what they call censorship of literature by promoting books that have landed on the challenged list.

Publishers, bookstores and libraries are hosting events countrywide such as panel discussions, symposiums and "read outs," or live readings, to draw attention to these books and "celebrate the freedom to read."

"Of course, not every book is right for each reader, but everyone should have an opportunity to choose for themselves," said ALA President Sari Feldman. "Librarians, booklovers and First Amendment supporters understand the importance of our freedom to read, and continue to work diligently to protect it and inform the public of its value."

The list of last year's most challenged books was released in April. Books featuring Native Americans, on-the-run alien lovers, gay penguins and middle school theater geeks topped the ALA's 2014 list.

Read More