On Wednesday night at the Yung Wing School, a public elementary school in Chinatown, students performed songs from the Disney musical “Mulan,” dancing crisply in traditional silk costumes ironed that morning by their parents. These were the voices of the next Asian-American generation in New York City — and they were loud.

Granted, many of them did not fully grasp the significance of Mayor Bill de Blasio’s announcement the day before: Lunar New Year will now become an official public school holiday.

But their parents and community leaders did. It had taken 10 years to get the winter holiday on the calendar, the culmination of a persistent campaign by a handful of officials and advocates representing a divided and often politically reticent population.

“It makes us proud that the city is paying attention to us — and our holiday,” Wendy Lam, 48, the mother of a fifth-grade actor, said in Mandarin. “It’s an important day for families to be together.” She added in English: “So proud. We tried to get the holiday for so many years.”