On Valentine’s Day, 17-year-old Jaclyn Corin, student president of her year at Marjory Stoneman Douglas high school in Parkland, Florida, was delivering carnations to raise prom funds. Then the shooting started. As a former student went on a rampage that left 17 people dead, Corin took refuge in a classroom with other terrified pupils. Down the corridor, Delaney Tarr, also 17, was hiding in a cupboard with friends from her journalism class. Over the next few weeks, Corin and Tarr, alongside other Parkland students, turned a life-changing tragedy into March For Our Lives, one of the biggest youth protests in the US since the Vietnam war.

Delaney Tarr Everyone involved in March For Our Lives mobilised as a way of processing our grief. It was pretty much the only thing we felt we could do in those moments after the shooting. That same night I was scheduling interviews with other students at the vigil the next day, because as a student journalist it was what I knew I could contribute.

Jaclyn Corin I’m more of an organiser. The day after the shooting, I started working on a trip to our state capitol in Tallahassee to lobby politicians. I was posting about that trip when my friend Cameron [Kasky] called me to come over to his house. There were six other people there already, working on the living-room floor. Over the next few days, more students joined and we formed the March For Our Lives movement. We were working furiously, trying to keep up the momentum, because the world was watching us. We knew we needed to take that attention and make it something positive. We said, “No! You’re not going to cover Parkland the way you covered Columbine 20 years ago, or how you covered Sandy Hook six years ago. Something is going to change because of this moment.”

DT The way the media covers gun violence is not necessarily productive – they’re looking for the sobbing victims. Instead, we took our anger and began to channel that. We really strategised about the message that became March For Our Lives.

JC Delaney actually made a “no-no list”. What words not to use when we were talking. Back then, it felt like it was interview after interview after interview. We had to make sure we were all on the right message if we wanted to move the needle.

DT For example, we always try to stay away from the term “gun control”, because people get triggered by the word “control”. They think we are trying to take all their guns, which isn’t the case. We’re trying to “prevent gun violence”.

JC Along with the no-no list, one of the most important things we did was have a rule that every interview had to mention the words “March 24th” [the day of the protest]. We wanted to make sure the world marched with us and March 24th was drilled into the minds of every person on this Earth. That was successful, because we had about 900 marches alongside the one in Washington DC. More than 2 million people marched with us as a cumulative total: we had marches from London to Mumbai, and in places that we hadn’t even heard of.

Facebook Twitter Pinterest Delaney Tarr (on left) and Jaclyn Corin. Photograph: Jeffery Salter for the Guardian

The students’ two-day lobbying trip to Tallahassee took place on 20 and 21 February, just six days after the shooting. One hundred students had more than 70 meetings with state representatives to discuss reforming gun legislation.

JC The Tallahassee trip was kind of my baby. The young people came into our state legislature and scared the shit out of them – I apologise for cursing. It was vital in our understanding that this is going to be a really difficult uphill battle, because politicians sometimes don’t want to talk to us. They don’t care how we feel. So it’s going to take constant energy from us to make sure that they keep listening. So we went to DC next.

On 26 and 27 February a group of Parkland students met elected officials in Washington DC to discuss gun reform.

DT In DC we came into every single meeting with the same message, the same policy points. We told them, “We are working against the NRA, we want you to stop being backed by the NRA.” We did not pull back. I don’t think a lot of them were ready for that. There were a lot of conversations where they seemed dismissive, both in Tallahassee and DC. I remember we met with one person and he was like, “Oh, so there’s going to be 1,000 people at your march?” I was like, “Well, 100,000 people are already confirmed at this point.” So yeah… That was actually our senator.

JC Oh my God, it was!

DT And there was a meeting with [House speaker] Paul Ryan, where we could tell we weren’t being listened to. Ryan was talking about how we need to focus solely on the mental health aspect of this, and not on gun legislation. And Alex Wind [another Parkland student] said to him, “Well, what about the Las Vegas shooter? He had no history of mental illness.” And Ryan says: “Yeah, you’re right.” And then he just ignored that point.

Not all the meetings went well, but we left feeling empowered, not downtrodden. We knew we had to work even harder, we had to do this on our own. We had to rally an army of young people ready and willing to vote out corrupt leaders.

The culture has changed: young people are finding civic engagement cool

JC For us it was a given that March For Our Lives would be inclusive. We know gun violence affects so many communities besides ours, and in so many different ways. It made sense to reach out to kids in other cities, who have been organising for years longer than us. It made sense to take our platform, that we had been given largely because we were white and affluent, and to share it.

DT If you look at the history of other movements, all of the successful ones have been intersectional. If you look at the civil rights movement, it was people of all backgrounds, standing and fighting alongside black people. And so March For Our Lives is about coming together as one American people.

On 24 March, five weeks after the shooting, the March For Our Lives protest took place in Washington DC and in cities across the world.

DT The number of people at the march was a little stressful. I remember I thought, “When I go out on stage, I won’t be nervous at all.” And then I walked out and I couldn’t see the end of the crowd. And moments later my speech flew across the stage and I had to run after it. I actually don’t remember giving my speech; my brain just couldn’t comprehend it. But I remember one of my favourite moments was when we all went out on stage with Jennifer Hudson, all looking out over this crowd of people who were there because they wanted to make a difference. I thought, “OK, this is real, we’re doing this.”

JC March For Our Lives continued after that day. We spent our entire summer travelling to communities around the country. We’ve met with other gun violence survivors, student organisers and leaders. We went to colleges and registered tens of thousands of voters. In November, we had the highest voter turnout [for midterm elections] in the US in over a century, and gun violence is the number one motivator for young people to get politically active in this country now.

DT So the culture around this has definitely changed and young people are starting to find civic engagement actually cool.

JC March For Our Lives is an ongoing movement. We have hundreds of chapters around the country, working on gun violence prevention in their communities. We’re already working on projects for 2019 and building young people as a stronger political force. Until this problem is fixed, we’re not going anywhere.

DT Exactly what she said.

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