A public showdown over the role of sexual orientation and gender identity in public education is looming at Tuesday’s Charlotte-Mecklenburg school board meeting.

The board is scheduled to vote on a revised multiculturalism policy that expands the definition of diversity and strengthens the mandate to “intentionally (incorporate) diversity throughout the curriculum, instruction, and professional development.”

But first board members will hear from the public. Both the Raleigh-based North Carolina Values Coalition, which opposes the change, and MeckPAC, a local LGBTQ rights group that supports it, are urging people to make their views known.

The board held its first public hearing on the change Jan. 9. Only half a dozen people, all students and parents who support the change, spoke then.

But the controversy comes as no surprise. CMS faced protests from the Values Coalition in 2016, when then-Superintendent Ann Clark revised the district’s anti-bullying policy to add protections for transgender students.

And in March 2017, the school board delayed putting the multiculturalism policy up for a hearing and vote, fearing that uproar over LGBTQ issues would distract from work on student assignment changes.

When the Values Coalition learned that the policy was on the January agenda and had already been through the first of two hearings, the group accused CMS of trying to “sneak through yet another attempt to rob parents of their rights to teach their kids about sensitive moral questions.” The group has been urging people to contact the CMS board and speak at Tuesday’s hearing to oppose a policy that would “affirm and promote homosexuality and transgenderism.”

In response, MeckPAC urged people to make signs and “fill as many seats as we can.”

A Facebook post warned MeckPAC supporters to expect bigotry from the Values Coalition and urged them not to respond in kind.

“For signs, we want to have messages that are targeted at CMS and don’t acknowledge the hate in the room,” the post said. “Messages like ‘Thank you, CMS!’ and ‘We support inclusion!’ are what we are going for.”

Anyone who wants to speak about the policy can sign up in advance by calling 980-343-5139 option 4, by noon Tuesday, or do so on site before the meeting begins. This meeting, which starts at 6 p.m. at the Charlotte-Mecklenburg Government Center, does not include an open forum for comments on general topics. It will be broadcast live online and on CMS-TV Cable 3.