Gay rights advocates sued Florida Gov. Ron DeSantis on Thursday to block a new law that forbids classroom instruction on sexual orientation and gender identity in kindergarten through third grade.

The law has catapulted Florida and DeSantis, a potential 2024 Republican presidential candidate, to the forefront of the country's culture wars. Critics call it the " Don't Say Gay " law and argue that its true intent is to marginalize LGBTQ people and their families.

The challenge filed in federal court in Tallahassee on behalf of Equality Florida and Family Equality alleges that the law violates the constitutionally protected rights of free speech, equal protection and due process of students and families.

"This effort to control young minds through state censorship — and to demean LGBTQ lives by denying their reality — is a grave abuse of power," the lawsuit says.

"The United States Supreme Court has repeatedly affirmed that LGBTQ people and their families are at home in our constitutional order. The State of Florida has no right to declare them outcasts, or to treat their allies as outlaws, by punishing schools where someone dares to affirm their identity and dignity," the lawsuit says.

The law deliberately employs broad terms and invites arbitrary and discriminatory enforcement, empowering parents to be roving censors who can sue school boards for damages based on any perceived violation, the lawsuit adds.

The law states: "Classroom instruction by school personnel or third parties on sexual orientation or gender identity may not occur in kindergarten through grade 3 or in a manner that is not age appropriate or developmentally appropriate for students in accordance with state standards." Parents would be able to sue districts over violations.

U.S. Education Secretary Miguel Cardona met with LGBTQ students and their family members at a school in Orlando on Thursday, discussing privately how the legislation is affecting their lives. Cardona's visit was one of several Biden administration events Thursday showing support for the queer community, including a presidential proclamation recognizing Transgender Day of Visibility.

"We know while many transgender students experience valuable support at school, many others face significant challenges because of hostility directed at them by others," Cardona said. "This includes a growing number of state laws that bully and intimidate LGBTQI+ students and their families."

DeSantis and other Republicans have repeatedly described the rules as reasonable, saying children should learn about sexual orientation and gender identity from their parents, not in schools.

"We will make sure that parents can send their kids to school to get an education, not an indoctrination," the governor said when he signed it into law this week.

Many critics have said the law's language, particularly the phrases "classroom instruction" and "age appropriate," could be interpreted so broadly that discussion in any grade could trigger lawsuits, creating a classroom atmosphere where teachers would avoid the subjects entirely.

Intense public backlash followed the bill's introduction in Florida's Republican-controlled legislature this year, with the White House, Hollywood celebrities, students, Democrats and LGBTQ advocates condemning the policy. Legal challenges have been expected.

The filing by Kaplan Hecker & Fink LLP and the National Center for Lesbian Rights seeks to block the law from taking effect and also names Florida Education Commissioner Richard Corcoran and other education officials as defendants.

"Already, our children have told us that they are afraid that they will not be able to talk about their family at school," Dan and Brent VanTice, parents of two first-grade students, said in the statement announcing the suit. "We are heartbroken that our children are already feeling isolated and stigmatized by this law."

Andrew Spar, president of the Florida Education Association union, said the law is politically motivated because elementary schools, especially in kindergarten through third grade, do not teach about these subjects and have state curriculum standards guiding classroom lessons.

The law adds fuel to a persistent feud between DeSantis and Democratic President Joe Biden, who tweeted after DeSantis signed the bill this week that "My Administration will continue to fight for dignity and opportunity for every student and family — in Florida and around the country." Cardona has said his agency will be monitoring for any federal civil rights violations that result.

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