JoAnne Bland was eleven years old when she marched over the Edmund Pettus Bridge in Selma, Ala. in a now-famous march for voting rights that has come to be known as Bloody Sunday. She was a busy member of the Student Non-violent Coordinating Committee, so March 7, 1965, was shaping up to be just another day in the movement. “All the kids marched. We loved it. We sang songs, we felt important.” They were also prepared. “We’d always been told if we were threatened to drop to our knees and start to pray. But that day, something went wrong.”

I had interviewed Bland in the months after the attacks on September 11, 2001, as part of an extended road trip/writing project about Americans and their stories. At the time, she was the lone steward of Selma’s tiny Voting Rights Museum, a small but sincere assemblage of exhibits that aimed to keep the Selma stories alive, in a world before Ava DuVernay. (Back then, some of the exhibit labels were just post-it notes. The museum seems to have grown substantially.) But sitting with her, just steps away from the famous bridge, was the first time that I fully understood how integral kids and teens have been to the success of important social movements.

The Washington Post’s Steven Levingston reminds us of the Children’s Crusade, a public protest against segregation held in May 1963, in Birmingham. Like the Selma march two years later, law enforcement brought the pain. “Birmingham’s brutal public safety commissioner, Eugene ‘Bull’ Connor, was waiting. His police moved in, herding the children into squad cars, paddy wagons and school buses for the trip to jail,” he writes.

And then the world saw this:

When the students kept coming, Connor turned fire hoses on them, knocking the children to the ground and spinning them down the street. To fight the high-powered blasts, some children joined hands trying to keep their balance in a human chain. But the torrents were too fierce; hit by the rocket-bursts of water the kids whirled one way, then the other, dragging down their comrades.

Decades later, the students of Marjory Stoneman Douglas High in Parkland, Fla., filmed their own horrific attack at the hands of a heavily armed former student. And the Florida students are now facing down trolls on social platforms, the full court press of media attention, and unspeakable grief to deliver their own call to action.

Stoneman Douglas High student Cameron Kasky is one of the organizers of “March For Our Lives,” a movement for gun control that prioritizes the lives of students and teachers. (It’s one of three student-led protests planned in the wake of the Florida school shooting.) From their mission statement: “March For Our Lives is created by, inspired by, and led by students across the country who will no longer risk their lives waiting for someone else to take action to stop the epidemic of mass school shootings that has become all too familiar.” One of their tactics is very specific: To stop politicians from taking money from the National Rifle Association, and to unseat any candidate who does in the upcoming mid-term elections.

The Florida students are showing the kind of courage that would resonate with JoAnne Bland.

https://twitter.com/BegorFlynn/status/965220368725266433

Listen to survivors. #ParklandStudentsSpeak pic.twitter.com/yqa9NWek8k

— Everytown (@Everytown) February 21, 2018

https://twitter.com/cameron_kasky/status/966299442788872193

While the Selma protestors were beaten back by the National Guard — Bland’s sister got 18 stitches that terrible day – the horror of the televised images shocked a nation into action. “We got the attention of the world. Dr. King came. Harry Belafonte came. They all came.”

Now, for the Florida students, money is coming. George and Amal Clooney just gave $500,000 to the March For Our Lives organization, and Oprah Winfrey and Steven Spielberg quickly matched the donation.

And increasingly, students across the country are organizing their own marches, lobbying efforts, and fundraisers for gun control in America under the hashtag “Never Again.”

“History shows that kids, with their innocence, honesty and moral urgency, can shame adults into discovering their conscience,” says Levingson.

Expect more discovery ahead. “People are watching. And if anything, I’m very excited to get back to school and be with the community and be around everybody supporting each other. Because one of the best things to come out of this horrible tragedy is the fact that Parkland has stayed strong,” said Kasky on Meet The Press. “And we’re not going to let the 17 bullets we just took take us down. If anything, we’re going to keep running, and we’re going to lead the rest of the nation behind us.”

Ellen McGirt writes Fortune’s raceAhead, a daily newsletter about race and culture.