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In this task, you are given a text of many news articles seperated by special token "|||||". Your task is to summarize them.

On Feb. 14, a gunman walked into Marjory Stoneman Douglas High in Parkland, Fla. and shot and killed 17 people, including 14 students. 
  
 The aftermath of the tragic shooting followed similar patterns: politicians sent their thoughts and prayers to the victims and discussed “the difficult issue of mental health“, and the price of shares in gun manufacturers went up. But students are responding to the tragedy in a more organized and national way than the country has seen in many years. 
  
 Activating the Activists 
  
 A group of students of Marjory Stoneman Douglas High who survived the shooting have started an organization called “March for Our Lives.” Their mission statement emphasizes the need to make the lives of students and teachers the nation’s “top priority” and calls on students across the country to join their cause. Some members of the group have spoken at gun-control rallies and have meetings with state officials planned for this week. They have their sights set on Washington, D.C., next. 
  
 The Walk-Out 
  
 The biggest action March for Our Lives has planned so far is a national student walk-out on March 24. The organizers and their families will be in Washington, D.C., on that day to meet with lawmakers, and they’ve invited students from around the country to join them, either in D.C. or in their own communities. One of the organizers, Cameron Kasky, said their goal is to stop politicians taking money from the National Rifle Association, and to unseat any politician who does in the upcoming mid-term elections. 
  
 Allies 
  
 March for Our Lives is not the only group that has planned a national walk-out in the wake of the shooting in Florida. The Women’s March youth branch, EMPOWER, is calling on “students, teachers, and allies” to walk out for 17 minutes (one minute for each victim) on March 14, a month after the shooting. Another group is planning a national walk-out on April 2o, which marks 19 years since the 1999 Columbine High School mass shooting, in which 12 students and one teacher were killed. ||||| Teens Hold 'Lie-in' Gun Control Protest at White House High school students organized on social media and held a "lie-in" protest Monday outside the White House. They told News4's Meagan Fitzgerald they want common-sense gun law reforms to protect children and teens. (Published Monday, Feb. 19, 2018) 
  
 Dozens of teenagers laid down in front of the White House Monday afternoon for three minutes. That's how long it took a gunman to kill 17 people on Wednesday at Marjory Stoneman Douglas High School in Parkland, Florida. 
  
 The teens held a "lie-in" on Presidents Day to demand that President Donald Trump and Congress change gun laws to keep children safe. 
  
 The group that organized the protest, Teens for Gun Reform, had called for 17 teens to lie on the ground, representing each victim of the high school shooting. But once those 17 people lay down, many more teens and adults joined them. 
  
 Teens Lie Down Outside White House, Demand Gun Law Changes 
  
  
  
 Some of the people who laid on the ground closed their eyes. Some crossed their arms over their chests, as if in a casket. At least two of the young people held hands. 
  
 Ella Fesler, a 16-year-old high school student in Alexandria, Virginia, said she participated because she was angry and afraid. 
  
 "It's really important to express our anger and the importance of finally trying to make a change and having gun control in America," she said. 
  
 "Every day when I say bye to my parents, I do acknowledge the fact that I could never see my parents again," she added. 
  
 DC Teens Stage ‘Lie-in’ in Support of Fla. Shooting Victims 
  
 Seventeen teens from the D.C. area held a three-minute “lie-in” outside the White House in support of the Florida shooting victims. (Published Monday, Feb. 19, 2018) 
  
 Two high school juniors, Whitney Bowen and Eleanor Nuechterlein, both 16, helped organize the protest via social media. 
  
 "We were completely inspired by the kids from Parkland speaking out," Nuechterlein said. 
  
 Raw Video: Teens Hold Gun Control 'Lie-In' Outside White House 
  
 Dozens of teenagers lay down in front of the White House on Monday to urge President Donald Trump and Congress to "protect kids, not guns." Here's the solemn moment they lay down. (Published Monday, Feb. 19, 2018) 
  
 In a statement, Teens for Gun Reform said, "We call on President Trump and leaders from both parties to finally act in the interest of America’s youth and end these tragic mass shootings! It is imperative that American children are safe in their classrooms, churches, malls, movie theaters and streets!” 
  
  
  
  
  
 During the teens' demonstration, Trump was at his Florida golf club, some 40 miles from the site of the school shooting. 
  
  
  
 Copyright Associated Press / NBC4 Washington |||||
Output:
The movement of young people demanding tougher gun laws after last week's shooting in Florida arrived at the White House Monday, where teens staged a "lie-in" to represent those shot at Marjory Stoneman Douglas High School, reports NBC4 Washington. "It's really important to express our anger," says a 16-year-old participant from Alexandria, Va. "Every day when I say bye to my parents, I do acknowledge the fact that I could never see my parents again." Here's a closer look at the movement—this speech by student Emma Gonzalez went viral over the weekend—and some analysis on why it may not be dissipating any time soon: Three national protests: Fortune rounds up future protest plans, including student walkouts planned for March. Post-Columbine: In the Washington Post, Philip Bump notes that today's high school students have never known a world where school shootings didn't exist, and that these survivors are different from those at Columbine, Newtown, and Virginia Tech. "This is the first premeditated mass shooting at this scale that involved people who both grew up entirely in a world in which mass shootings were common and which targeted people old enough to have a voice."