Marissa Levendis's father served in the Vietnam War. Her uncle was killed in Vietnam.

So as President Bush's call for war against Iraq grows more insistent, Levendis, a senior at Yorktown High School in Arlington, knows what she is going to do: protest. At 2:30 this afternoon, Levendis and many of her classmates plan to walk out of class to demonstrate their opposition to an invasion of Iraq.

"High school students should be involved because we are the ones who are going to fight this war," said Levendis, who has joined peace marches and helped collect classmates' signatures on petitions. "This will affect us sooner or later."

Today's high school students were in grade school when Bush's father declared war in the Persian Gulf in 1991. They became teenagers in an era of relative peace and prosperity, when many of them could regard war as the province of computer games or history class.

Now a new generation of students have been introduced to the prospect of war, every day more probable, and they are apprehensive, uncertain and curious, talking about it among themselves in classrooms, at lunch and online.

"This is very much on their minds," Arlington School Board member Mary H. Hynes said. "For kids, particularly high school kids, the world as they know it has been turned upside down."

Two weeks ago, the perennially youthful MTV, where many young people get their information, conducted a national survey in which respondents said war in Iraq was foremost on their minds, surpassing the economy, sex, peer pressure and violence.

"Iraq was the top issue, and it's the first time a political issue has been number one," said Jane Sangster, vice president of MTV News. She added that even after Sept. 11, 2001, fear of terrorism came behind sexual issues and drug abuse in MTV polls. "It's touching their lives, and they are talking about it."

And some are acting. George Levendis, 60, said he supports his daughter's protest because of the questions it helps raise. "I don't think there has been enough debate -- we seem to be the only country not discussing it enough," said Levendis, who was a Marine in 1965-66. "Given the experience of Vietnam, if nothing else, we ought to be very careful about what we do."

Elizabeth Black, 17, a senior at the Madeira School in McLean, and Mike Pilat, 17, a senior at Bishop Ireton High School in Alexandria, said Iraq and North Korea's nuclear capabilities were the dominant topics among the 2,000 students who attended a recent world-issues conference sponsored by Georgetown University.

But even in more mundane settings, in discussions with his friends at school, "it comes up almost on a daily basis," Pilat said. "The draft comes up a lot."

As co-founder of Youth Advocates for Awareness, Black said she and her peers are trying to learn as much as possible about the current conflict. "It's an obligation to know what's going on about the invasion," Black said. "This is going to directly affect our generation."

As a managing editor of Young D.C., a monthly regional newspaper for teenagers, Clio Andris, 18, said the editorial staff is trying to figure out ways to explain war-related issues to people who might know a lot or know nothing at all about how a war would affect them.

Andris, a senior at Winston Churchill High School in Potomac, said the staff is preparing a story about the Selective Service System, which requires all male U.S. citizens ages 18 to 25 to register in case they are needed in a military emergency.

Although the draft was ended after the Vietnam War, Rep. Charles B. Rangel (D-N.Y.) introduced a bill in Congress in January that would reinstate the draft and require young men to enlist in the military through a lottery as they did during the Vietnam War.

"Some of the guys don't know about the Selective Service, because until now war has not been an issue," Andris said.

MTV's Sangster said the station will be expanding its coverage of Iraq because viewers are asking about the prospect of war. They're asking "basic questions: Who is Saddam Hussein? Why are they doing this now?" Sangster said. "It's become important to them."

As a result, MTV has even sent its own correspondent, Gideon Yago, 25, to report from Kuwait.

Many teachers also have taken the opportunity to teach about a region their students once didn't know or care about. John Hart, a social studies teacher at Arlington's Swanson Middle School, recently held a mock U.N. assembly at which 78 eighth-graders debated invading Iraq.

"This was an opportunity to connect the curriculum to real life," Hart said. He recounted a recent exchange with some students who were in his class last year who hadn't believed him when he said Iraq would become important again.

"It was like they were listening to a crazy aunt," he said, adding that they came back to tell him he'd been right. And because they are in the Washington area -- considered a prime target for terrorists -- he said he detects a growing concern and anxiety among his students.

"They're beginning to get a sense that they are at Ground Zero," he said. "They are asking, 'What if we get attacked again?' "

Hynes, the School Board member, agreed that students are beginning to feel bombarded: first the Sept. 11 terrorist attacks in 2001, then the sniper attacks that killed 10 people in the Washington area during a terrifying month last year and now the prospect of war.

"In a very short time, these kids have experienced sudden and unexpected dangers," she said. "I think kids are just trying to figure out how to be in this world that, after September 11, changed in just a few minutes."

Yorktown High seniors Maya Mackrandilal, left, and Marissa Levendis gathered signatures from 500 students opposed to a war against Iraq.