San francisco gay pride parade
Men wave rainbow and 'black lives matter' flags while marching in the annual LGBTQI Pride Parade on Sunday, June 25, 2017 in San Francisco, California. The LGBT community descended on Market Street for the 47th annual Pride Parade. (Photo by Elijah Nouvelage/Getty Images)

A school in the Sacramento area is being criticized after a teacher was accused of throwing away students’ projects on the Black Lives Matter movement and informing students that the social justice group is “inappropriate” subject matter.

According to The Hill, on Thursday, a letter from the American Civil Liberties Union (ACLU) claims that in September a teacher from the Del Paso Manor Elementary School assigned a project instructing students to create art about causes they care about.

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The directions were that the students choose “something they wanted to see change in their school,” according to the letter addressed to Kent Kern, the San Juan Unified School District’s superintendent.

The assignment was given as a follow-up to a lesson plan delivered by a parent volunteer titled “Art can manifest in activism – can manifest in our communities and school.”

That parent addressed immigration and housing rights, pay equity, animal rights, reforming financial aid, and the Black Lives Matter movement, the letter continued. However, when four students created posters supporting the Black Lives Matter movement, a teacher identified as “Mr. Madden” allegedly threw the art away and made the students redo the assignment.

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He also allegedly banned the parent volunteer who encouraged them from returning to the class. Even after Madden, “demanded answers regarding why a presentation on Black Lives Matter was relevant to Del Paso Manor Elementary,” he was backed by school authorities for what appeared to be a bias against the group.

The ACLU says the school’s principal “backed Mr. Madden by irrationally stating that Black Lives Matter lessons are political statements and therefore off limits for public display.”

They also pointed out that posters and speech about Black Lives Matter are protected speech under California law for both the student and the dismissed parent volunteer. So the school district removing the art is “an impermissible viewpoint restriction,” given they aren’t legally allowed to “single out” those projects.

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The letter requested a public apology from the school district, asked that the parent volunteer be allowed to continue volunteering at the school and suggested that cultural and sensitivity training for staff and parent engagement training.

They also suggest that faculty “hang the Black Lives Matter posters up during the Spring Art Night (if the students want to remake them) that has a Black Lives Matter theme.”

NBC News reports that after pushback from the ACLU, the district issued a statement acknowledging, “It is inconsistent with our values and never our intent or desire for any student to feel uncomfortable or unwelcome to discuss issues that are important to them,” the district said in the statement. “We sincerely apologize if this experience made any student feel such discomfort. Censoring a student’s assigned work because of its content would not be acceptable.”