WASHINGTON — The Supreme Court on Tuesday rejected the appeal of a Massachusetts student who was barred from wearing a T-shirt to school proclaiming there are only two genders.

The justices left in place a federal appeals court ruling that said it would not second-guess the decision of educators in Middleborough, Massachusetts, to not allow the T-shirt to be worn in a school environment because of a negative impact on transgender and gender-nonconforming students.

Educators at the John T. Nichols Middle School barred the student from wearing the T-shirt and an altered version with the words “two genders” covered up by tape with the word “censored” written on it.

Justices Samuel Alito and Clarence Thomas dissented.

The court should have heard the case, Alito wrote, noting that “the school permitted and indeed encouraged student expression endorsing the view that there are many genders,” but censored an opposing view.

“This case presents an issue of great importance for our Nation’s youth: whether public schools may suppress student speech either because it expresses a viewpoint that the school disfavors or because of vague concerns about the likely effect of the speech on the school atmosphere or on students who find the speech offensive,” Alito wrote.

The 1st U.S. Circuit Court of Appeals said it was reasonable to predict that the T-shirt will “poison the educational atmosphere” and disrupt the learning environment.

The school district’s decision was in line with a landmark Supreme Court ruling from 1969, Tinker v. Des Moines Independent Community School District, that upheld the right of public school students to wear black armbands to protest the Vietnam War when it did not create a substantial disruption to education.