The <a href="http://www.ala.org/bbooks/about" target="_blank" target="_blank">American Library Association</a> reports that "offensive language," "sexually explicit" material and books that are "unsuited to age group" are the top reasons cited for challenging books in schools and libraries.<br /><br />On the association's <a href="http://www.ala.org/advocacy/banned/frequentlychallenged/21stcenturychallenged" target="_blank" target="_blank">annual list of top 10 challenged books</a>, Dav Pilkey's "<a href="http://www.pilkey.com/" target="_blank" target="_blank">Captain Underpants" series</a> ranked No. 1 in 2012 because of "offensive language" and because it is "unsuited to age group."
10 most challenged books of 2012 —
The American Library Association reports that "offensive language," "sexually explicit" material and books that are "unsuited to age group" are the top reasons cited for challenging books in schools and libraries.

On the association's annual list of top 10 challenged books, Dav Pilkey's "Captain Underpants" series ranked No. 1 in 2012 because of "offensive language" and because it is "unsuited to age group."
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"The Absolutely True Diary of a Part-Time Indian," Sherman Alexie's young adult novel about a Native American teen who attends an all-white high school, was challenged in at least three English classes at a New Jersey high school in 2012. Complaints noted "sensitive material in the book including excerpts on masturbation amongst other explicit sexual references, encouraging pornography, racism, religious irreverence and strong language," <a href="http://www.ila.org/BannedBooks/BBW_2012-2013_Shortlist.pdf" target="_blank" target="_blank">according to an ALA report</a>.
10 most challenged books of 2012 —
"The Absolutely True Diary of a Part-Time Indian," Sherman Alexie's young adult novel about a Native American teen who attends an all-white high school, was challenged in at least three English classes at a New Jersey high school in 2012. Complaints noted "sensitive material in the book including excerpts on masturbation amongst other explicit sexual references, encouraging pornography, racism, religious irreverence and strong language," according to an ALA report.
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References to suicide, drugs, alcohol and smoking were among the examples cited in challenges to Jay Asher's young adult novel, "Thirteen Reasons Why." Complaints said it contained material that was sexually explicit or unsuited to the age group.<br /><br />From 2000 to 2009, the ALA has counted 1,577 challenges due to "sexually explicit" material and 1,291 challenges for offensive language.
10 most challenged books of 2012 —
References to suicide, drugs, alcohol and smoking were among the examples cited in challenges to Jay Asher's young adult novel, "Thirteen Reasons Why." Complaints said it contained material that was sexually explicit or unsuited to the age group.

From 2000 to 2009, the ALA has counted 1,577 challenges due to "sexually explicit" material and 1,291 challenges for offensive language.
Penguin Group
The ALA's <a href="http://www.ala.org/bbooks/frequentlychallengedbooks" target="_blank" target="_blank">Office for Intellectual Freedom </a>compiles lists each year of frequently challenged books in schools and libraries based on media reports and <a href="http://www.ala.org/bbooks/challengedmaterials/reporting/online-form" target="_blank" target="_blank">reports submitted to to the association</a>. <a href="http://www.cnn.com/2013/08/14/showbiz/celebrity-news-gossip/james-50-shades-top-earner-ew/index.html">E.L. James</a>' "Fifty Shades of Grey" made its debut on the list this year based on complaints citing offensive language and sexually explicity material.
10 most challenged books of 2012 —
The ALA's Office for Intellectual Freedom compiles lists each year of frequently challenged books in schools and libraries based on media reports and reports submitted to to the association. E.L. James' "Fifty Shades of Grey" made its debut on the list this year based on complaints citing offensive language and sexually explicity material.
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After one year off the list, Peter Parnell and Justin Richardson's "And Tango Makes Three" is back among the most-challenged books. The 2005 children's book is based on the true story of a pair of male penguins at the Central Park Zoo who hatched an egg together. The book has generated acclaim and controversy based on challenges that it is "unsuited for age group." In 2012, it was marked for removal in the Davis, Utah, school district because parents might find it objectionable, according to the ALA.
10 most challenged books of 2012 —
After one year off the list, Peter Parnell and Justin Richardson's "And Tango Makes Three" is back among the most-challenged books. The 2005 children's book is based on the true story of a pair of male penguins at the Central Park Zoo who hatched an egg together. The book has generated acclaim and controversy based on challenges that it is "unsuited for age group." In 2012, it was marked for removal in the Davis, Utah, school district because parents might find it objectionable, according to the ALA.
simonandschuster
<a href="http://www.cnn.com/2013/06/24/living/hosseini-mountains-echoed-refugee/index.html">Khaled Hosseini</a>'s award-winning novel "The Kite Runner" was challenged in 2012 as optional reading in 10th-grade honors classes in schools in Troy, Pennsylvania, because the novel depicts rape in graphic detail and uses vulgar language.
10 most challenged books of 2012 —
Khaled Hosseini's award-winning novel "The Kite Runner" was challenged in 2012 as optional reading in 10th-grade honors classes in schools in Troy, Pennsylvania, because the novel depicts rape in graphic detail and uses vulgar language.
Penguin Group
John Green's "Looking for Alaska" was banned as required reading in 2012 in schools in Sumner County, Tennessee, because of "inappropriate language." The coming-of-age tale about a teen who falls in love at boarding school won the ALA's 2006 Michael Printz award for the best book written for teens.
10 most challenged books of 2012 —
John Green's "Looking for Alaska" was banned as required reading in 2012 in schools in Sumner County, Tennessee, because of "inappropriate language." The coming-of-age tale about a teen who falls in love at boarding school won the ALA's 2006 Michael Printz award for the best book written for teens.
Penguin Group
Alvin Schwartz's "Scary Stories" books have terrified children since the 1980s. To this day, they remain the subjects of challenges from some who consider them too violent and unsuited for age group.
10 most challenged books of 2012 —
Alvin Schwartz's "Scary Stories" books have terrified children since the 1980s. To this day, they remain the subjects of challenges from some who consider them too violent and unsuited for age group.
HarperCollins
Jeannette Walls' 2005 best-seller "The Glass Castle" recounts her experience growing up with an alcoholic father and a mother who suffered from mental illness. It has been the target of perennial challenges and a few bans for its explicit language, references to child molestation, adolescent sexual exploits and violence. In 2012, a Traverse City, Michigan, school board <a href="http://detroit.cbslocal.com/2012/12/11/michigan-school-board-rejects-book-ban-request/" target="_blank" target="_blank">rejected a request to remove the book</a> from an English reading list.
10 most challenged books of 2012 —
Jeannette Walls' 2005 best-seller "The Glass Castle" recounts her experience growing up with an alcoholic father and a mother who suffered from mental illness. It has been the target of perennial challenges and a few bans for its explicit language, references to child molestation, adolescent sexual exploits and violence. In 2012, a Traverse City, Michigan, school board rejected a request to remove the book from an English reading list.
scribner
Toni Morrison's Pulitzer Prize-winning novel "Beloved" has made frequent appearances on the ALA's most frequently challenged list. In 2012, parents in Salem, Michigan, asked that it be removed from an Advanced Placement English class on the grounds that it contained sexually explicit and violent content. District officials determined the novel was appropriate for the students' age and maturity level, <a href="http://www.ila.org/BannedBooks/BBW_2012-2013_Shortlist.pdf" target="_blank" target="_blank">according to the ALA</a>.
10 most challenged books of 2012 —
Toni Morrison's Pulitzer Prize-winning novel "Beloved" has made frequent appearances on the ALA's most frequently challenged list. In 2012, parents in Salem, Michigan, asked that it be removed from an Advanced Placement English class on the grounds that it contained sexually explicit and violent content. District officials determined the novel was appropriate for the students' age and maturity level, according to the ALA.
Knopf Doubleday Publishing Group