Students from Marjory Stoneman Douglas school in Parkland, Florida are thanking businesses for supporting their calls for gun reform.

A slew of businesses cut ties with the National Rifle Association, raised the age they would sell guns to 21, or spoke out in support of gun control after the shooting at the school on February 14.

The high schoolers became activists after a gunman killed 17 of their classmates and teachers. They're hosting a rally in Washington, DC on March 24.

A Letter to the Business Community From Marjory Stoneman Douglas Survivors and #NeverAgain Movement Founders,

First of all, thank you. My friends and I are humbled, awed and deeply grateful for the support the business community has put into ensuring that tragedies like the one that happened at our school never happen again. Despite the grief and trauma and confusion we feel, we are inspired daily by the courage from leaders like you. We are on the right side of history and together we can lead the way.

Thank you to Walmart, Dick's Sporting Goods and L.L. Bean. Thank you to Delta and United Airlines. Thank you to Enterprise Holdings, Hertz, and Avis Budget. Thank you True Car. Thank you Kroger. Thank you to Black Rock, First National Bank of Omaha, and Symantec.

Thank you to REI. Thank you to Lockton, MetLife, Paramount RX, SimpliSafe, and Starkey. Thank you to Lyft, Bumble, Aetna, and Gucci. Thank you to the leaders in the Gun Safety Alliance. And thank you to the hundreds of businesses and individual leaders who acted on their consciences and took positive steps for change.

Mourners visit a memorial for Jaime Guttenburg, one of the 17 victims of the Parkland shooting. Joe Raedle/Getty Images

We'd like to ask more businesses to support our movement by taking actions they believe in. One way you can help us is to support the March For Our Lives on Saturday, March 24th in Washington D.C. We have had an extraordinary outpouring of generosity and have raised just over $3 million on our GoFundMe campaign. But it turns out marches are really expensive, and we want this march to be a seismic moment of change in this country.

And we don't want it to be about us. We want it to be about all of the survivors — the schools and families who had to come before us – as well as honoring the innocent lives lost. The kids in Chicago, Detroit, Baltimore and other cities who live through a siege of gun violence EVERY DAY. The students around the country who don't want it to happen to them next.

So please help us. Adopt a school in your area who wants to attend the March For Our Lives in Washington and pay for them to do it. Donate buses, flights, train tickets. Donate your time or your talent, or donate directly to March For Our Lives at www.marchforourlives.com.

For this to really be Never Again, we all have to stand together. Students, businesses, survivors, elected officials, leaders... we invite everyone to participate in our movement, even if you don't agree with everything we say. Believe me, we don't always agree with each other. But we know what's happening today can't stand. We know we want it to change. And we know this is just the beginning.

Let's do this.

Signed,