Every few weeks or months, after a man armed with a high-powered weapon walks into a school or a church or a nightclub and opens fire, the national response plays out in a rote, almost performative way. The outcry lasts only a few days before guns fade back into the background noise of American politics.

But nearly three weeks after a gunman walked into Marjory Stoneman Douglas High School in Parkland, Florida, and killed 17 people with an AR-15, the conversation has not faded, because the students of Stoneman Douglas have taken up the cause of gun control. Already, they have lobbied state lawmakers in Tallahassee, spoken with President Donald Trump and persuaded many companies to cut ties with the National Rifle Association. And on Saturday, they met with students fighting gun violence in Chicago.

Several of those students, and their critics, have noted the incongruity of teenagers getting involved in politics. But history is full of movements led by students — albeit usually in college, not high school. Some were successful and others brutally crushed, but even the latter still resonate.

(Most of these campaigns have been liberal-leaning: Though conservative college students have made their presence known, their actions have rarely coalesced into broader movements.)

Here are seven other cases where young people were moved to challenge adult society.

GREENSBORO SIT-INS, 1960

The lunch counter sit-ins that would change U.S. history began with four teenagers who walked up to a Woolworth’s lunch counter in Greensboro, North Carolina, and refused to leave.

Those young men — Ezell Blair Jr., 18; Franklin McCain, 19; Joseph McNeil, 17; and David Richmond, 18, all students at North Carolina Agricultural and Technical State University — made their stand on Feb. 1, 1960. Within three days, they were joined by some 300 others. By summer, the sit-ins had spread to more than 50 cities, and lunch counters were rapidly desegregating.

The actions of the so-called Greensboro Four led directly to the creation of the Student Nonviolent Coordinating Committee, which the civil rights organizer Ella Baker urged students to form in April 1960 to coordinate the continuing sit-ins. Later, SNCC would play a major role in the Freedom Rides and in voter registration efforts across the South. And the momentum that began at the Woolworth’s lunch counter would eventually contribute to the passage of the Civil Rights Act of 1964, which outlawed segregation in public spaces.

Perhaps more than anything, the results of the Greensboro sit-ins showed the power of a small group of students prepared to stand alone if necessary.

“Inevitably, people ask me, ‘What can I do?’” McCain said in an interview in 2005. “What kind of question is that? Look around you. Once you identify what you want to do, don’t ask for the masses to help you, because they won’t come.”

UNIVERSITY UPRISINGS, 1968

In the spring of 1968, student protests exploded on multiple continents. Some accomplished their stated goals and others did not, but even the latter contributed to a climate in which change seemed possible and more people were inspired to act.

In March, more than 1,000 students at the historically black Howard University took over the administrative building, and many more barricaded themselves in their dormitories. They demanded that the university president resign; that the curriculum emphasize African-American history and culture; that a judiciary system involving students be created; and that disciplinary proceedings against students involved in an earlier protest be dropped. The university agreed to the third and fourth demands.

Students at Columbia University used similar tactics a month later, occupying several buildings for a week before 1,000 police officers stormed the campus to evict them. Strikes continued for the rest of the semester, essentially paralyzing the university even after the occupiers were cleared out. The students were protesting two things — the construction of a university gym in Morningside Park in Harlem that would provide only limited access to Harlem residents, and Columbia’s Vietnam-era contract with a weapons research think tank — and Columbia canceled both.

On the other side of the Atlantic, students revolted in France and Poland. In Warsaw, protests against government censorship built from 300 students in January to 20,000 in March, but were ultimately suppressed. And in Paris, some 20,000 swarmed the Sorbonne in May, turning cars into barricades and clashing with riot police. French labor unions and teachers joined a 24-hour general strike in support of the students, bringing the nation to a grinding halt but failing to topple President Charles de Gaulle.

APARTHEID DIVESTMENT, 1970s-80s

As with the Greensboro sit-ins 16 years earlier, the uprising started by public school students in Soweto, South Africa, would expand far beyond them.

On June 16, 1976, several thousand students near Johannesburg began a peaceful march that turned deadly when the police attacked with guns and tear gas. The protesters were objecting to a law that mandated Afrikaans-language education, but they set in motion a global movement against apartheid. Images of police brutality — particularly a photograph of a high school student carrying the body of Hector Pieterson (12 or 13 years old; accounts differ) — drew international attention to the broader cruelty of South Africa’s government.

From the actions of the students of Soweto grew a vast campaign led by college students in the United States, who built shantytowns on campus quads, blockaded buildings and disrupted speeches by South African politicians. From Columbia University to the University of California, protests compelled administrators to withdraw billions of dollars in investments from companies tied to South Africa. Over time, the resulting economic stress contributed, along with other factors, to the dismantling of apartheid.

TIANANMEN SQUARE, 1989

On June 4, 1989, several weeks of student-led pro-democracy demonstrations in Beijing ended in slaughter when thousands of Chinese troops began firing on crowds of protesters in Tiananmen Square. Hundreds of people, possibly thousands, were killed; a death toll was never released.

Nearly 30 years later, China is still not a democracy. Its trend, on display in 1989, of allowing economic but not political liberalization continues. And in some ways, the protests had the opposite of their intended effect: The crackdown provided a visceral demonstration of how far the government would go to suppress dissent, which discourages some would-be activists to this day. But an iconic image from June 5, of a lone, still unidentified man standing in front of a column of tanks, endures as an emblem of defiance in the face of overwhelming odds.

VELVET REVOLUTION, 1989

Eight days after the Berlin Wall fell, signaling the beginning of the end of East Germany’s communist government, the students of neighboring Czechoslovakia stepped in to topple their own.

The uprising began with thousands and grew until Prague was flooded with 500,000 protesters, who stayed stubbornly peaceful even as riot officers attacked, giving the revolution its name. Just 11 days after the protests began, the Communist Party of Czechoslovakia relinquished power, paving the way for the playwright Vaclav Havel to become president in December.

It was an extraordinary revolution — “swift, entirely nonviolent, joyful and funny,” said author Timothy Garten Ash — and one of the most rapid and complete successes for a student-led movement in modern history.

IRAN, 1999

After a series of scuffles between college students and the police in July 1999, officers raided a dormitory at the University of Tehran, wounding at least 20 people and jailing 125. If their goal was to stop the unrest, the police could not have gone more astray: In response, more than 10,000 Iranian students took to the streets.

In the short term, the protests forced officials, including President Mohammad Khatami and Ayatollah Ali Khamenei, to condemn the police raid. The ayatollah urged restraint even if students “set my picture on fire or tear it,” a remarkable directive from a government not normally tolerant of political dissent.

But perhaps more important were the long-term consequences. Since Iran’s 1979 revolution, student activists had generally been tied to political parties. After the 1999 protests, that ceased to be the case. And while Iran’s society and politics remain tightly regulated, the tradition of student activism has continued there, more so than in many countries with similar political systems.

BLACK LIVES MATTER, 2013-PRESENT

The Black Lives Matter movement began with three women in their late 20s and early 30s: Patrisse Cullors,Alicia Garza and Opal Tometi. But when it exploded into national view in 2014 after the police killing of Michael Brown, 18, many of the protesters who filled the streets of Ferguson, Missouri, were students.

Like the students of Parkland, they were protesting gun violence — but by the police, often involving unarmed black suspects, in shootings captured on video. Unlike the students of Parkland, they were not lauded in the prevailing public narrative, a discrepancy that some Black Lives Matter activists have noted in recent weeks. Instead, they were frequently labeled troublemakers and thugs.

But even as questionable police shootings happen, convictions of officers remain rare, and protests on the streets continue, Black Lives Matter has had a fundamental impact on the national conversation about racial bias and the use of excessive force by the police.

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