Powerful images of students holding hands and hoisting signs: This is what a nationwide walkout looks like

Show Caption Hide Caption Students across country walk out to demand change This is what a nationwide walkout looks like.

Students across nearly 3,000 schools marked National Walkout Day on Wednesday, with classrooms nationwide emptying at 10 a.m. local time in a call to end gun violence.

Demonstrations at most schools lasted 17 minutes — one for each victim killed in the February shooting at Marjory Stoneman Douglas High School.

Wednesday's protests mark the first of several events throughout March and April organized by students as part of the #NeverAgain movement. Another walkout is slated for April 20 to remember the 19th anniversary of the Columbine High School massacre.

Here are images and videos from Wednesday's protests at schools across the nation.

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Eastern High School in Washington, DC

Harvest Collegiate High School in New York City.

Marjory Stoneman Douglas High School in Parkland, Fla.

Center for Inquiry School 2 in Indianapolis

Outside the White House in Washington, DC

Dickinson High School in Wilmington, Del.

Stivers School for the Arts in Dayton, Ohio

James Ferris High School in Jersey City, N.J.

Rousseau McClellan Montessori School 91 in Indianapolis

Pioneer High School in Ann Arbor, Mich.

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