Aly Conyers was supposed to spend the summer competing at track and field meets.

Instead, the 17-year-old all-American sprinter stood in front of a crowd of hundreds near Howard University earlier this week. Her older brother, Ace, had planned on leading the Sunday afternoon protest, but he had lost his voice from shouting in front of the White House. So Aly, who attends a private high school in South Carolina, stepped onto a brick platform, grabbed the megaphone, and started speaking.

“We are the face of this movement,” she shouted to the crowd. “We are the face of this generation. We will not let this stand. Enough is enough.”

Hours later, Aly coughed and wheezed in a cloud of chemical gas near the White House. On Monday, she ran as federal law enforcement officers fired rubber bullets to clear demonstrators from Lafayette Square. On Thursday, she returned to the protests yet again, leading a crowd of more than a thousand people at the Martin Luther King Jr. Memorial in a moment of silence.

Across the country, thousands of teenagers like Aly are on the front lines of the protests demanding justice for George Floyd and other victims of police brutality.

For many, their high school years in the age of Trump, #MeToo and the Parkland shooting have been punctuated by protests — the Women’s Marches, March for Our Lives, racial justice and climate change rallies. They were in elementary school when Trayvon Martin was shot and killed, and grew up knowing his name, along with the words his death helped ignite: Black Lives Matter.

But most have never come face to face with police officers in riot gear, or with military vehicles lining the streets.

“It was terrifying,” Aly said about Monday’s ambush by the Secret Service, U.S. Park Police and National Guard. “It was like something out of a movie scene. Everyone went moving backwards and crying."

In Minneapolis, Chris Owusu, 17, was chanting George Floyd’s name outside the police department’s 3rd Precinct station last week when he was blind sided by tear gas, he said. His eyes burned. His lungs felt as though they were collapsing.

“It’s the most excruciating pain that I’ve ever felt,” he said.

He was about to go home when he noticed his friend had been shot with a rubber bullet on the side of her forehead. Blood was gushing down her face, and she was having trouble speaking. He offered to drive her to the hospital, maneuvering his car through the massive crowds flooding the streets of Minneapolis.

“I will have one hell of a college essay to write,” Owusu said.

Choked by gas, hit by rubber bullets, knocked down by officers’ shields, they have continued to come back, in many cases taking leading roles in the protests. On Saturday, they will be there again for what is expected to be the largest gathering yet.

The images of teenagers being roughed up by police officers evokes memories of the Children’s Crusade in 1963, when more than a thousand black students skipped class for a civil rights march in Birmingham, Ala. Police aimed fire hoses at them, launching them onto the street. Some of the children joined hands, forming a human chain to fight the blasts.

Aly Conyers, 17, spoke at the Martin Luther King Jr. Memorial in Washington, D.C., on June 4, encouraging people to "elect the right person who can protect us." (Samantha Schmidt/The Washington Post)

In 1963, involving children in the protests was a strategy by the movement’s leaders. But more than a half-century later, teenagers at the George Floyd protests are stepping up on their own, risking exposure to the coronavirus and projectiles from police, defying curfews and, in many cases, the wishes of their parents.

Naomi Spates, 17, didn’t tell her mother she was going to the protests Tuesday with a friend. Naomi, a rising senior at Bladensburg High School in Prince George’s County, Md., was in middle school when she joined hundreds of thousands of people at the Women’s March on the Mall the day after President Trump’s inauguration. In the years since, she has condemned gun violence at the March for Our Lives, and denounced white supremacists at a counter-demonstration. But the George Floyd protests, she said, have felt different.

“There has never been military posted up, telling us we have a curfew, putting up gates at the White House,” she said, “basically telling us what we’re doing is wrong.”

On Tuesday, at the U.S. Capitol, she stood a foot away from a row of police on the other side of a barricade and asked a black officer, “Do you have any children?”

“Yes, I have two daughters, he responded to her.

“Look at us, we’re the same as your daughters,” Naomi told him. “It could happen to them just like it could happen to us.”

At the Lafayette Square barricades, Roberto Rivera, 14, put on a gas mask from a military surplus store that was too big for his head. His school, D.C. International, had canceled classes for the day to support the protests on Blackout Tuesday.

“Once I saw the military police lining up with their shields,” he said, “I didn’t know if they were going to fire.”

He used his spare bottle of water to wash out pepper spray from a woman’s eyes.

The images from that day are now seared in his memory, changing his view of police and military officers. “I don’t feel as safe near them anymore,” he said.

Zoe Willcutts, 18, was protesting at Lafayette Square in Washington, D.C., on June 3 when an officer fired a pepper ball that struck her in the face. (The Washington Post)

Zoe Willcutts has been marked by the violence, physically and emotionally. The 18-year-old from Takoma Park, Md., was kneeling and holding her hands in the air 10 feet away from the fence at Lafayette Square just before 1 a.m. Wednesday when an officer fired a pepper ball that struck her in the face. Her nose and eyes began burning intensely. A golf ball-size welt rose up from her jaw. A friend poured water into her bloodshot eyes.

“No one was doing anything to them. No one got near them,” she said of the police. “They’re bullies and they want you to be scared.”

Aly grew up surrounded by officers in uniform. Her father was in the Army, and her family has lived on military bases in Toronto, Seoul and Guantánamo Bay, Cuba. She has been raised with deep respect for the military, but also with an understanding of racial injustice in the world. Her father encouraged her to read James Baldwin and Malcolm X from a young age. She vividly remembers her first protest: She was about 11, on vacation in Chicago, when her family decided to join a Black Lives Matter march.

Aly doesn’t agree with some of the posters she’s seen demanding to “Abolish The Police.” But she understood their anger and pain as she marched with a group of about 200 protesters down Constitution Avenue on Wednesday, passing Humvees and military officers at nearly every intersection.

As her group reached the U.S. Capitol, she joined as they took a knee in front of a row of police officers on the other side of the barricade.

“Who do you protect?” they shouted. “Who do you protect?”

In response to what she’s witnessed, Aly created a group with her brother and a friend called Faces of the Future, hoping to get teenagers like her more involved beyond the protests in D.C.

On Thursday, as members gathered in the shadow of the Martin Luther King Jr. Memorial, Aly stood in front of an even bigger crowd than the one at Howard University.

“I stand here as a 17-year-old who won’t be able to vote in the next election, asking you … asking the people older than me to vote for me,” she said into the megaphone. “Use my voice to use your voice to elect the right person who can protect us.”

She looked around her and saw hundreds of teenagers who had joined the protest after seeing the flier on social media or hearing about it from friends. In the 90-degree heat, they all took a knee as Aly read the list of names of those who have died: Freddie Gray, Sandra Bland, Alton Sterling, Philando Castile.

The crowd remained silent for 8 minutes 46 seconds, marking the amount of time the white police officer pressed his knee on George Floyd’s neck.

Then the protesters rose and began marching.

Rebecca Tan, Marissa Lang and Peter Jamison contributed to this report.