By Agence France-Presse
The "March for Our Lives" will take place on March 24, with sister rallies planned across the country, a group of students told ABC News' "This Week."
They pledged to make Wednesday's slaughter in Parkland, Florida a turning point in America's deadlocked debate on gun control.
Nikolas Cruz, 19, a troubled former student at Marjory Stoneman Douglas High School, confessed to killing 17 people with a legally-purchased AR-15 semi-automatic rifle, the latest such atrocity in a country with more than 30,000 gun-related deaths annually.
Among the students announcing the march was Emma Gonzalez, who captured worldwide attention with a powerful speech in which she assailed President Donald Trump over the multi-million-dollar support his campaign received from the gun lobby.
She vowed Stoneman Douglas school would be "the last mass shooting."
On Sunday, Gonzalez, 18, urged politicians to join a conversation about gun control -- citing Trump as well as his fellow Republicans Florida Senator Marco Rubio and Governor Rick Scott.
"We want to give them the opportunity to be on the right side of this," she said, as she and her four classmates called on students nationwide to help push the message.
White House 'listening session'
Gonzalez and other Stoneman Douglas students were scheduled to be part of a nationally televised, prime-time "town hall" event on CNN on Wednesday. Rubio, who has attracted criticism for accepting millions in political help from pro-gun groups, tweeted that he would participate.
That same day, Trump will host a "listening session" with high school students and teachers, the White House said in a statement, though it did not specify who would attend.
The president met Sunday with top Republican lawmaker Paul Ryan, discussing "the recent tragedy in Parkland, Florida," among other topics.
Singling out links between politicians and the powerful National Rifle Association, Stoneman Douglas student Cameron Kasky said any politician "who is taking money from the NRA is responsible for events like this."
"This isn't about the GOP," he said, referring to the Republican Party. "This isn't about the Democrats."
The NRA, a traditional ally of the Republicans who currently control Congress and the White House, defends a literal view of the US Constitution's 2nd Amendment which promises a right "to keep and bear arms."
Even after last October's killing of 58 people by a gunman in Las Vegas who amassed 47 firearms to commit the worst mass shooting in recent US history, legislators accomplished nothing in the way of tighter controls.
Accusing the NRA of "fostering and promoting this gun culture," Kasky said the students seek "a new normal where there's a badge of shame on any politician who's accepting money from the NRA."
'They want action'
"People keep asking us, what about the Stoneman Douglas shooting is going to be different, because this has happened before and change hasn't come?" said Kasky.
"This is it," he continued. "We are going to be marching together as students begging for our lives."
The students did not indicate how many people they expected to join their rallies.
But their aims won support from Florida Democratic Congressman Ted Deutch, who said they can make a difference.
"After what they saw, the worst things imaginable, they're not going to just sit back and take it," he told "This Week."
"All I've heard all week is how frustrated people are with rhetoric. They want action."
Florida Republican Congressman Carlos Curbelo, speaking on the same program, said he is working towards bipartisan solutions that could prevent similar tragedies.
"There are a lot of Republicans who are prepared to support reasonable, common-sense gun safety laws," he said.
Democratic Congressman Adam Schiff said that although Republicans have faced a bigger hurdle in making gun control a priority, "it's been a challenge in the Democratic Party as well."
Speaking on CNN's "State of the Union," Schiff asked, "How much more of this are we gonna to take? How many more shootings?"
Congress has to get "off its backside" to "stare down the NRA and do the right thing," he said.
The student survivors' calls for change "should matter," said Mark Kelly, a retired astronaut whose wife, former congresswoman Gabrielle Giffords, was shot and wounded by a deranged gunman.
He said on "Fox News Sunday" that the student activists "are going to vote on this issue probably for the rest of their lives and they're going to encourage others to do that as well."
But conservative radio host Rush Limbaugh, speaking on the same show, said neither legislation nor marches are the answer.
"It's not the fault of the NRA," he said, calling for concealed weapons to be allowed in schools.
"If we are really serious about protecting the kids, we need a mechanism to be defensive."