After a two-year effort to urge state lawmakers to officially declare Sept. 21 Peace Day, Holbrook students celebrated with an assembly in which speakers urged them to be the change they wish to see, said teacher Mary Clougher. About 160 students gathered on the day in question in the school auditorium to hear from Norfolk District Attorney Michael Morrissey, state Senator John Keenan, and Bill Richard, father of Martin Richard, the 8-year-old boy who was killed in the Boston Marathon bombing in 2013. Keenan sponsored a bill, signed into law in December, that officially recognizes Peace Day, which the United Nations also recognizes Sept. 21. Students in the sixth-grade civics club, inspired by the Martin Richard Bridge Builder Campaign, which encourages children and adults to foster kindness and compassion, came up with the idea for a Peace Day in Holbrook, said Clougher, their club adviser. In support of their efforts, the students filmed a public service announcement about peaceful responses to recent violent attacks, and also testified in front of a Senate subcommittee on the importance of establishing a Peace Day. “They want to be the generation that wants to solve things by peaceful means,” Clougher said.Jill Terreri Ramos can be reached at email@example.com. Follow her on Twitter @jillterreri.