Organisers behind the Women's March, an anti-Trump and female empowerment protest, called for a 17-minute walkout on March 14 to "protest Congress inaction to do more than tweet thoughts and prayers in response to the gun violence plaguing our schools and neighbourhoods."
The Network for Public Education, an advocacy organization for public schools, meanwhile, announced a "national day of action" on April 20, the anniversary of the 1999 shooting at Columbine High School in Colorado, in which two students opened fire on their classmates, killing 12 students and one teacher.
"The politicians sit on their hands as our children and their teachers are murdered in their schools," Diane Ravitch, the groups president, and Carol Burris, its executive director, said in a post online.
The protest plans circulated widely on social media on Saturday, signaling that the outcry for new gun legislation may not fade away as it has after other recent mass shootings.
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Many of those shootings, including the deaths of 20 first-graders and six educators at Sandy Hook Elementary School in Newtown, Connecticut in 2012, led to a push for new gun laws, but those efforts stalled in Congress.
Weingarten said she was part of the discussions about the April 20 protest. What gives the Florida shooting more potential to spark change, she said, is that the students themselves got angry really quickly and demanded it.
Teenage survivors of Wednesdays shooting at Marjory Stoneman Douglas High School have become advocates for gun control, sparring with gun-rights activists on social media and calling for safer gun laws at vigils and in television interviews.
Some people in online posts called for a Civil Rights-era style boycott of schools until gun laws are changed. David Berliner, a professor of education at Arizona State University who also participated in the plans for the April 20 protest, said he would support such a boycott.
He recalled watching a television news report about Wednesdays shooting at an airport.
"I am crying, and Im watching all the people all around me crying, and I just said, This has got to stop," he said.
She said a private Facebook page she launched announcing a meeting of her Stop School Shootings group after the Florida shooting attracted more than 7,000 followers overnight. Her protest is planned for March 14.