American free speech organisations are fighting a decision by a New Jersey school to remove a critically acclaimed anthology of writing about teenage homosexuality from library shelves after parents described it as vulgar and obscene.

Revolutionary Voices, a collection of stories, poems and artwork by young homosexuals, was banned at Rancocas Valley Regional High School last week following a campaign by the local chapter of Glenn Beck's conservative 9.12 project. Local grandmother and 9.12 member Beverly Marinelli told the Philadelphia Inquirer that the book was "pervasively vulgar, obscene, and inappropriate", while insisting that she is "not a homophobe".

But a coalition of free speech groups has jumped to the book's defence, saying that residents "have no right to impose their views on others or to demand that the contents of the library reflect their personal, religious, or moral values".

"There are undoubtedly GLBTQ [gay, lesbian, bisexual, transgendered, and questioning] students at Rancocas Valley High School, regardless of whether they are openly recognised. Removing any of these titles would send a clear message to those students that they are the objects of social disapproval – different, vulnerable, and marginal – whose needs for information of particular relevance to their lives are not respected," wrote the directors of a collection of organisations to the school's board. The letter, the signatories to which include the National Coalition Against Censorship, the National Council of Teachers of English, American Booksellers Foundation for Free Expression, the Association of American Publishers and PEN America, added that there was "no question that these books are not obscene".

"No one has to read something just because it's on the library shelf," the letter continued. "No book is right for everyone, and the role of the library is to allow students to make choices according to their own interests, experiences, and family values ... Even if the books are too mature for some students, they will be meaningful to others."

Lambda Legal, a US civil rights group representing gays, lesbians, and people with HIV/Aids, has also written to the school board saying that removing the book "undermines the school's obligation and ability to protect students regardless of sex, sexual orientation, or gender identity".

The book's editor, Amy Sonnie, pointed to a letter from a 15-year-old boy, who said that on reading the volume he was relieved to discover "that there were other people out there who shared elements of my identity".

"Queer students may not feel safe speaking up when LGBTQ books are challenged," said Sonnie. "But, they certainly deserve a chance to discover the 'diversity of voices' that make balanced library collections so crucial for the health of our communities and democracy."

The Philadelphia Inquirer reported that the local 9.12 group is now looking to get the same book removed from the Lenape regional high school district, the county's largest school district. But the paper said that students were "shrugging off" the controversy. "Just because these books are in the library isn't going to cause us to be gay," they said. "We have so much access to information, if we want to read something we'll read it."