The U.S. Department of Justice has launched an investigation into four California school districts over policies pertaining to the instruction of gender and sexual orientation.

On Monday, the agency said the San Francisco Unified School District, along with the Graves Elementary School District, Santa Rita Union School District and Soledad Unified School District are undergoing a compliance review. The department’s Civil Rights Division said the review pertains to “instruction on sexual orientation and gender ideology (SOGI) in grades pre-K-12.”

“This Department of Justice will not tolerate local school authorities trampling on the rights of parents concerning the education of their children,” said Assistant Attorney General Harmeet Dhillon.

Officials said the review will examine whether, and to what extent the districts notified the parents of their right to opt their children out of such instruction. In its statement, the agency alleged that San Francisco Unified advised its teachers that neither parental permission nor notification were required to teach or discuss the topics.

The compliance review would also assess policies regarding access to bathrooms, locker rooms and girls’ sports teams based on gender identity rather than biological sex, along with adherence to Title IX, officials said.

“The Supreme Court’s recent decisions in Mahmoud and Mirabelli have put all school districts on notice: policies that keep parents in the dark about sexuality and gender ideology in the classroom must end now,” Dhillon added, citing two recent rulings by the Supreme Court.

In Mahmoud vs. Taylor, the justices last year sided with a group of Maryland parents who challenged their school district’s decision to deny them the ability to opt out their elementary children of instruction featuring storybooks addressing gender identity and sexual orientation.

Earlier this year, in the Mirabelli vs. Bonta case, the justices blocked a California state law that bans parental notification requirements if students change their pronouns or gender expression at school.

According to the California Department of Education, San Francisco is the sixth largest public school district in the state, with about 55,000 students.

The three other districts being investigated are in Monterey County. State records show Soledad Unified serves about 4,600 students in and around Soledad, while Santa Rita Union serves about 1,200 students in a portion of Salinas. Graves Elementary serves about 30 students at one school campus in Salinas.

CBS News Bay Area has reached out to the districts for comment.