Demonstrators are seen in downtown San Francisco to take part in the 'March for our Lives' event on Saturday, March 24, 2018.none
Jay Leno is pictured with Mayor Dianne Herrin of West Chester, Pa. during a March for Our Lives event on March 24, 2018.WPVI
People hold banners during the "March For Our Lives" event in Paris, France, Saturday, March 24, 2018.AP
People hold banners during the "March For Our Lives" event in Paris, France, Saturday, March 24, 2018.AP
Demonstrators cheer outside city hall during the March for Our Lives protest for gun legislation and school safety, Saturday, March 24, 2018, in Cincinnati.AP
Dezmond Floyd, center left, joins in the march in downtown Houston during a March for Our Lives protest for gun legislation and school safety Saturday, March 24, 2018.AP
Houston Police Chief Art Acevedo, Houston Mayor Sylvester Turner, and Rep. Sheila Jackson Lee, D-Texas, join demonstrators during a March for Our Lives protest in Houston.AP
Demonstrators gather outside the downtown Houston office of Sen. Ted Cruz, R-Texas, during a March for Our Lives protest for gun legislation and school safety.AP
Protesters gather for the March for Our Lives rally along Pennsylvania Avenue March 24, 2018 in Washington, DC.none
Participants take part in the March for Our Lives Rally in New York on March 24, 2018.none
Holding pictures of victims killed in gun violence, thousands of people, many of them students, march against gun violence in Manhattan.none
A student from Baltimore, Maryland, holds a protest sign during the March for Our Lives Rally in Washington, DC on March 24, 2018.none
Participants take part in the March for Our Lives Rally in Washington, DC on March 24, 2018.none
Participants arrive for the March for Our Lives Rally in Washington, DC on March 24, 2018.none
The crowd at the March for Our Lives Rally as seen from the roof of the Newseum in Washington, DC on March 24, 2018.none
Protesters hold signs aloft as they attend the "March for Our Lives" rally in support of gun control in Washington.AP
Daisy Hernandez, 22, of Stafford, Va., wrote "Don't Shoot," on her hands during the "March for Our Lives" rally in support of gun control, Saturday, March 24, 2018, in Washington.AP
People hold their hands up with messages written on them during the "March for Our Lives" rally in support of gun control, Saturday, March 24, 2018, in Washington.AP
Demonstrators gather during the March for Our Lives protest for gun legislation and school safety outside city hall, Saturday, March 24, 2018, in Cincinnati.AP
Demonstrators gather during the March for Our Lives protest for gun legislation and school safety outside city hall, Saturday, March 24, 2018, in Cincinnati.AP
A sign from Maryland's Great Mills High School is seen in the crowd during the "March for Our Lives" rally in support of gun control, Saturday, March 24, 2018, in Washington.AP
Participants gather during the March For Our Lives event, Saturday, March 24, 2018, in Parkland, Fla.AP
Participants gather during the March For Our Lives event Saturday, March 24, 2018, in Parkland, Fla.AP
Participants gather during the March For Our Lives-Parkland event Saturday, March 24, 2018, in Parkland, Fla.AP
Students from Great Mills High School in southern Maryland, protest during the "March for Our Lives" rally in support of gun control in Washington.AP
Steven Rothman, left, and Dan Knorowski attend the "March for Our Lives" rally in support of gun control in Washington, Saturday, March 24, 2018.AP
Crowds of people hold signs on Pennsylvania Avenue at the "March for Our Lives" rally in support of gun control, Saturday, March 24, 2018, in Washington.AP
Crowds of people hold signs on Pennsylvania Avenue at the "March for Our Lives" rally in support of gun control, Saturday, March 24, 2018, in Washington.AP
The stage area is set up on Pennsylvania Avenue near the U.S. Capitol in Washington, Friday, March 23, 2018, before the "March for Our Lives" rally in support of gun control.AP