As the shooting began, the teenagers captured the sound of gunfire on their phones. When it didn't stop, they texted their parents and took to social media to share each fearful moment with the outside world.
Then it was over and 17 people were dead. Within a day, as they continued to express their thoughts online and on air to reporters, the survivors' expressions of grief turned to calls for political action.
"Blood is being spilled on the floors of American classrooms, and that is not acceptable," David Hogg, a senior at Marjory Stoneman Douglas High School, said in an interview.
"By working through bipartisanship and working through our differences . ....