Urging high school seniors to flex their civic muscle, officials launched a citywide initiative Monday to register them to vote.

Chancellor Richard Carranza, Mayor Bill de Blasio, Deputy Mayor Phil Thompson and others encouraged Manhattan Hunter Science High School students to make their voices heard.

“I am just so moved by what I am seeing,” de Blasio said of recent student activism. “Yes, it’s the #MeToo movement, it’s the Black Lives Matter, it’s the Women’s Marches all over this country.”

New Yorkers are notorious for their civic lethargy — only 23 percent of registered voters cast a ballot in the race for de Blasio’s re-election, and the state ranked 41st in participation in the 2016 presidential election.