Your Guide to March for Our Lives Rallies From New York to L.A. – Time Magazine:

More than 500,000 people — in major cities like New York City, Boston, Chicago, Los Angeles and Portland — are expected to march in solidarity with the Florida shooting survivors to advocate for gun control and school safety.

Following the shooting — now the deadliest high school shooting in the country — the students from Parkland, along with students around the country, have been taking action: Visiting statehouses to demand legislative action, staging walkouts, and organizing marches.