SAN FRANCISCO — If Merry Susan Hyatt has her way, every public school pupil in California will have the voter-approved right to sing “Joy to the World” in the classroom.

Hyatt, 61, a substitute schoolteacher, is the chief proponent of a proposed California ballot initiative that would require the state’s public schools to offer Christmas music during the holiday season.

Hyatt said she was inspired to start her ballot drive after working at a school where only nondenominational songs were allowed at holiday parties. That struck her as unfair.

“We feel kids love Christmas,” she said. “And we’re not allowed to play Christmas carols. And we think that’s wrong.”

Secretary of State Debra Bowen said the proposal’s backers could start circulating petitions to get it on the ballot, though with some 434,000 valid signatures required, Hyatt has some work to do.

“We got 25 signatures in just two nights,” Hyatt said. “It goes really fast.”

Hyatt first proposed her law in a letter to the state attorney general in August, arguing that listening to Christmas music during the holidays was “a longstanding American tradition and a significant element of our cultural heritage.”