Myracle's series of books for young adults, about the dramas of three high school friends, Zoe, Maddie, and Angela, are written entirely in the style of instant messaging. "These books deal realistically with young adult lives – the ickyness, the weirdness of adolescence and the difficult situations lots of teens face," said Angela Maycock of the ALA's office for intellectual freedom.
Reasons given: Nudity, sexually explicit, offensive language, unsuited to age group, drugs Photograph: Public Domain
Parnell's and Richardson's tale of two male penguins bringing up an orphaned chick has topped the list for the last three years, but dropped to second place this year.
Reasons given: Homosexuality Photograph: AP
Chbosky's teenage narrator describes various scenes in his life and explores topics such as introversion, teenage sexuality, abuse, and drug use. Chbosky has cited Salinger's The Catcher in the Rye as an inspiration, and pays homage to it by naming it as one of the books Charlie's English teacher gives him to read
Reasons given: homosexuality, sexually explicit, anti-family, offensive language, religious viewpoint, unsuited to age group, drugs, suicide
Photograph: Public Domain
Harper Lee's Pulitzer Prize-winning story of rape and racial inequality in 1930s Alabama is a veteran of the most-challenged list, due to Lee's use of the word "nigger". "Similar to The Adventures of Huckleberry Finn, Lee uses the language of a certain time," Maycock acknowledges. "But the use is to put forward a very strongly anti-racist message. It is really a shame that one particular word makes a book objectionable when the message of the book is exactly the opposite."
Reasons given: Racism, offensive language, unsuited to age group Photograph: Getty Images
Meyer's novels about the romance between a human teenage girl and a vampire, reached the most-challenged list for the first time this year. "Books that are read frequently are frequently challenged," Maycock points out. "With all the hype around Twilight ... I was actually surprised Meyer's books weren't higher." Vampire books in general accumulated a host of complaints last year, with "the idea of vampires and other supernatural entities in opposition to certain religious viewpoints".
Reasons given: Sexually explicit, religious viewpoint, unsuited to age group Photograph: Public Domain
JD Salinger's iconic novel of teenage rebellion has provoked a storm of complaints – from being "anti-white" and "obscene" to being "centred around negative activity" and "a filthy, filthy book" – since its publication more than 50 years ago. It returned to the list of most challenged books this year after a four-year absence. "It's a cherished favourite for many readers so seeing it there can be shocking," says Maycock. "People might ask 'are we still having problems with Catcher in the Rye?' The truth is, yes we are. It's a classic because of many of the things that make it potentially objectionable, including the language used and the fact that Holden Caulfield is a classic non-conformist. That can be scary."
Reasons given: Sexually explicit, offensive language, unsuited to age group Photograph: Amy Sancetta/AP
Picoult's novel, which has since been made into a film in 2009, tells the story of 13-year-old Anna who sues her parents for medical emancipation when she is expected to donate a kidney to her sister Kate, who is dying from leukemia.
Reasons given: Sexism, homosexuality, sexually explicit, offensive language, religious viewpoint, unsuited to age group, drugs, suicide, violence Photograph: Public Domain
Mackler's Michael L Printz award-winning novel tells the story of high school student Virginia Shreves, who has a "larger-than-average" body and a medium-sized inferiority complex.
Reasons given: Sexually explicit, offensive language, unsuited to age group Photograph: Public Domain
Walker's most famous novel won the 1983 Pulitzer prize for fiction and the National Book Award, and has been adapted for stage and screen. Set in rural 1930s Georgia, it focuses on the position of black women in the southern US, and has frequently been targeted by censors since its publication.
Reasons given: Sexually explicit, offensive language, unsuited to age group Photograph: Public Domain
Cormier's young adult novel, set in the fictional Trinity High School and following hero Jerry Renault as he challenges the school's brutal mob rule, was first published in 1974, and was made into a film in 1988
Reasons given: Nudity, sexually explicit, offensive language, unsuited to age group Photograph: Public Domain
