Public schools in Maryland must allow parents with religious objections to withdraw their children from classes in which storybooks with L.G.B.T.Q. themes are discussed, the Supreme Court ruled on Friday.

The vote was 6 to 3, with the court’s liberal members in dissent.

The case extended a winning streak for claims of religious freedom at the court, gains that have often come at the expense of other values, notably gay rights.

The case concerned a new curriculum adopted in 2022 for prekindergarten through the fifth grade by the Montgomery County Public Schools, Maryland’s largest school system.

The storybooks included “Pride Puppy,” an alphabet primer about a family whose puppy gets lost at a Pride parade; “Love, Violet,” about a girl who develops a crush on her female classmate; “Born Ready,” about a transgender boy; and “Uncle Bobby’s Wedding,” about a same-sex union.

At first, the school system gave parents notice when the storybooks were to be discussed, along with the opportunity to have their children excused. But school administrators soon eliminated the advance notice and opt-out policy, saying it was hard to administer, led to absenteeism and risked “exposing students who believe the storybooks represent them and their families to social stigma and isolation.”

Parents of several faiths sued, saying the books violated the First Amendment’s protection of the free exercise of religion. The books, their complaint said, “promote one-sided transgender ideology, encourage gender transitioning and focus excessively on romantic infatuation.”