It's one of the most delicate and potentially combustible questions schools can face.

A teenager confides in a teacher that he or she is transgender and wants to transition at school without any family finding out about it.

Should the school call the student's parents? And, if it does, what happens if mom and dad say no?

After years of school officials using their own best judgment, New Jersey has weighed in, siding with students and telling schools they must allow kids to change genders -- even if their parents don't know about or don't want it to happen.

LGBT advocates are celebrating the new state guidance, saying it puts New Jersey among the national leaders in protecting transgender students from unaccepting or abusive parents. But parent and family groups argue schools should never keep such a significant and consequential secret from parents, who should have a right to know if their child says they are transgender.

"We always have believed that any discussion that affects our students should be an all-inclusive discussion," said Rose Acerra, president of the New Jersey PTA. "(We) could never fully support anything that leaves the parent voice out."

Of course, parental involvement is ideal, said Aaron Potenza of Garden State Equality, an LGBT advocacy organization. But that's not always best for the student, he added.

"If a student tells you, 'If my parents hear this they are going to throw me out,' then we don't want school districts notifying parents," Potenza said.

The debate is just the latest in a series of questions schools have grappled with involving transgender students and their rights.

What pronoun should teachers use when talking about the student? Which bathroom should a student use? What name should be printed in the yearbook?

Many of those questions were already answered through state law or prior federal guidance, said David Rubin, a longtime school board attorney for New Jersey districts.

But parents' right to have the final say over their child being recognized as transgender has remained "uncharted waters" legally, Rubin said. That's left school boards and their attorneys to navigate sensitive and complex cases based on their own interpretation of anti-discrimination laws.

Rubin and some other attorneys were already advising districts that parents don't necessarily have to be told their child is transgender or transitioning and also don't have to give permission, he said.

Though the new state guidance is not legally binding -- it's the Education Department's interpretation of a 2017 state law reinforcing transgender students' rights -- it is likely to be followed, Rubin said.

"It is something you can point to as at least some source of authority," Rubin said. "It provides guidance and cover for school districts who may have angry parents confronting them."

And it's likely that some parents will be angry.

Transgender teenagers can often face family rejection and are physically abused or kicked out of their home, said Brenda Barron, director of public policy for GLSEN, a national advocacy organization for LBTQ issues in education.

"The sad reality is that too many transgender and gender nonconforming youth may be placed in further danger by schools forcefully outing them to unsupportive family," Barron said.

That's what makes it so important that New Jersey schools don't require parental notification and consent, said Potenza, the director of programs for Garden State Equality.

LGBT advocates have turned to states to affirm transgender students' rights after the Trump administration rescinded federal guidance issued under during the Obama era.

They weren't the only ones looking to the state for answers, said Mike Yaple, a spokesman for the Department of Education.

"School districts have been asking for this guidance for some time," Yaple said.

The new guidance was drafted with the help of a task force that included state education organizations. It places the state among about a dozen others that have sent schools instructions for protecting transgender students following the removal of the federal guidance.

Only a few states among that group have told schools that parental notification is not required, and New Jersey's stance comes after some other states, including Delaware and Ohio, came under fire for proposals that would have reported transgender students to their parents.

"I would put this up there with the best of the best," Potenza said of New Jersey's guidance.

To be clear, the state is not saying schools are forbidden from telling parents that their students are transgender, Potenza said. And, in the case of disagreements between students and parents, the state says schools should provide information about family counseling and support services outside of the school district.

Still, the issue remains far from resolved.

Parent and family groups say they understand the concerns about student safety and don't want to see any kids get hurt. But they also think parents have a right to be notified by schools.

The New Jersey Family Policy Council, a conservative group that opposed the 2017 state law, called the new guidance "disturbing."

"Families should be involved in what's going," said Len Deo, the group's president. "This is an issue, I think, that's going to be very, very, controversial."

Adam Clark may be reached at adam_clark@njadvancemedia.com. Follow him on twitter at @realAdamClark. Find NJ.com on Facebook.