Starting this school year, the Oregon Department of Education required that each school district’s forms offer students and families at least three gender options: male, female and nonbinary, said its communications director, Marc Siegel. But Mr. Siegel noted that in Oregon, each school district can draft its own forms. Districts are encouraged to use the term “nonbinary” and not just have the third option be marking an “X” for gender, he said in an email.

In Washington, Mr. Wells said all schools already have all-gender restrooms. He said that the information collected from next year’s enrollment forms could be used to “ensure that more gender-neutral bathrooms are near multi-user restrooms to ensure students have the same path of travel as their peers. We could also ensure students have equitable access to sports and extracurricular activities.”

Some parents embraced the decision to change the enrollment forms to include nonbinary. .

“Seeing yourself represented intentionally on documentation — not just as a block that says ‘other’ — is a really good move,” said Adalphie Johnson, who has a daughter who graduated from a public school in Washington and a son who is currently a junior at one. Ms. Johnson is also the programs director at Supporting and Mentoring Youth Advocates and Leaders, which “supports and empowers lesbian, gay, bisexual, transgender and questioning youth” in the Washington metropolitan region.

“The form change might prompt parents to have conversations with their children about their gender identities, and it would help young people advocate for themselves,” Ms. Johnson said.

“I had three friends who were seniors last year who identify as nonbinary, and this would have made life so much easier for them since it would have formally recognized their preferred gender identity,” said Will Beckerman, a 15-year-old sophomore at School Without Walls High School in Washington, who identifies as a transgender male. He said the change would “help a lot of other kids understand what being nonbinary means.”