Melody Herzfeld, a drama teacher who hunkered with her students in a classroom at Marjory Stoneman Douglas High School in February as a gunman massacred 17 people in its hallways, accepted the excellence in theater education prize at the Tony Awards on Sunday evening.

She said that receiving the award, which is given annually to a K-12 theater teacher by the Tony Awards and Carnegie Mellon University, was one of her life’s most significant moments.

“Next to the passing of my dear parents and in-laws, marrying the love of my life and the birth of my amazing sons and reuniting with my theater students, there has never been a more defining moment of my life,” said Ms. Herzfeld, who is the director of the drama department at the Parkland, Fla., school.

“All the goodness and tragedy that has brought me to this point will never be erased,” she said from the stage at Radio City Music Hall, in Manhattan, ahead of the televised portion.

“I remember on Feb. 7, in a circle with my students, encouraging them to be good to each other,” she went on. “And I remember only a week later, on Feb. 14, a perfect day, where all these lessons in my life and in their short lives would be called into action.”

“We all have a common energy. We all want the same thing. To be heard. To tell our truth. To make a difference. And to be respected. We teach this every day in every arts class,” she said.

Ms. Herzfeld, who will receive a $10,000 prize for her theater program, has been responsible for more than 50 productions at Stoneman Douglas since 2003.

During the main event, Ms. Herzfeld’s students surprised the audience, singing an emotional rendition of “Seasons of Love,” from the musical “Rent.” They received a standing ovation, and left some in the crowd in tears.

Matthew Morrison, an actor who earned a Tony nomination in 2005 for his role in the musical “The Light in the Piazza,” introduced the performance.

From the stage, he told Ms. Herzfeld that a couple of months ago, he had performed with some of her students at a benefit concert for Parkland. “For us, it was a life-changing experience to see these inspiring young people channeling their intense feelings of hurt and rage and sorrow into art,” he said.

One of those students, Tanzil Philip, reached out to the Tonys, asking to appear on the telecast tonight, Mr. Morrison said.

“The Broadway community showed up in our time of need and brought some much-needed light into the dark,” Mr. Philip had written.

“Well, Tan, rather than inviting you on to this stage to say thanks to us, our Broadway family wants to give and say thanks to you, by sharing the stage with you and your classmates,” Mr. Morrison said.

Just a week after the shooting, Ms. Herzfeld’s students performed “Shine,” an original song, at a CNN town hall meeting on gun violence.

“We’re done with all your little games,” they sang. “We’re tired of hearing that we’re too young to ever make a change. You’re not going to knock us down. We’ll get back up again.”

In a statement in May, Ms. Herzfeld said that normally she would feel “humbled and grateful” to be recognized for her work, but that it “now means so much more” since her students “have taken to action through speech, performance and passionate honesty.”

Joshua Barone and Peter Libbey contributed reporting.