Chad Denis was hours into his first day as a student teacher at Brewer High School when the nation came under attack on Sept. 11, 2001.

The University of Maine student, already nervous about his first day in the classroom, heard from a secretary about the terror attack that killed nearly 3,000 Americans. A small black-and-white television at the school provided glimpses of the events unfolding in New York, Washington and Pennsylvania, but Denis didn’t really understand the full magnitude of what was happening until he went home that night.

“I don’t think it hit the kids, either,” he said. “In 2001, kids didn’t have phones. They weren’t pulling up all that information on Twitter.”

Eighteen years later, Denis is a government teacher at Old Orchard Beach High School and teaches students who were not yet born on Sept. 11, 2001. When the anniversary of the terror attacks comes around, he and fellow educators around Maine and across the country teach about something that is an unforgettable personal experience for them and an important historic event for their students.

Teachers and school administrators take a variety of approaches to the anniversary, weaving personal experience and a sense of the shock and fear that gripped the nation with an academic look at how the attacks shaped the country that students have grown up in. Some schools continue to hold a moment of silence on the morning of Sept. 11.

Most years, Denis shows his students videos related to 9/11 so students can experience the attacks the way people did when they watched them on TV at the time. They also talk about how the terror attack changed foreign policy. Earlier in his teaching career, conversations about 9/11 were different because it was still fresh in the minds of students who watched it unfold.

And, Denis said, “there are years I haven’t talked about it because I didn’t want to relive it.”

Kelli Deveaux, communications director for the Maine Department of Education and former Westbrook High School principal, said educators tell her that the conversation about 9/11 has evolved in schools. Students in elementary through high school today were not born and “do not have the context that those of us who lived through it do,” she said.

“It has become less about remembrance and more about teaching about a historic event,” she said.

The Portland Press Herald’s front page from Tuesday, Sept. 11, 2001. Brianna Soukup/Staff Photographe

Deveaux said some districts also are very careful “to ensure Muslim or Middle Eastern students are not harassed in misdirected response” to discussions about 9/11.

John Morgan, a teacher at Westbrook High School, said he usually takes 20 minutes during class to read excerpts from a Press Herald story detailing the timeline of the hijackers’ experiences in Portland the night before they flew to Boston and launched the attacks.

“As a sophomore-level teacher, the last time I had students in my classes who were alive on (Sept. 11, 2001) was a few years ago, so I’ve found this approach to be engaging because they’re often aware of the overall story but not Maine’s connection to the event,” Morgan said. “And the tick-tock with the names and the locations of local landmarks seems to really grab their attention and make it more relevant for them and allows them to make some connections to the event they might not otherwise make.”

Other teachers also say it’s the personal connections that keep the history lesson real.

“Our plan is to make a personal connection to 9/11 for the students,” said Sarah Bailey, chair of the history department at South Portland High School. Teachers usually start by sharing with students where they were when it happened and give an overview of the events and the aftermath. They then compare 9/11 to Pearl Harbor and talk about how both events changed the identity of the United States, she said.

This year, South Portland High School social studies teacher Richard Romanow came up with a presentation to serve as a guide for teachers throughout the district, realizing that many younger teachers were in middle school or even younger when 9/11 happened.

South Portland Superintendent Ken Kunin was principal at the Reiche Community School in Portland in September 2001 and remembers the impact on the community when it was learned two of the attackers had spent the night in Portland the day before the attack. “The kids had heard this person who perpetrated awful things was staying in their neighborhood, so that kind of brought it home as well,” he said.

Today, the South Portland district aims to share with students information about a “pivotal point in United States history” and give them the chance to discuss and ask questions in small groups, he said.

Teachers in Cape Elizabeth also have shared personal experiences with students. Mark Ashe, who teaches senior government at Cape, was teaching in upstate New York at the time and has shared with students the confusion, sense of loss and a feeling like being in a dream, and also the feeling of togetherness and desire to help.

Ashe said his seniors began research projects Tuesday and will give short presentations about the broad effects that the attacks have had on the U.S. political system, from the conflicts between security and liberty, to the Afghan invasion and negotiations with the Taliban, to the the reorganization of the federal government and creation of the  Homeland Security Dept., the Transportation Safety Administration and Immigration and Customs Enforcement, or ICE.

“Taken together, the goal is to give students a sense of how broadly the 9/11 attacks have impacted society, in some cases in ways that may not be immediately evident,” Ashe said.

In Regional School Unit 23, John Suttie, superintendent and principal of Old Orchard Beach High School, starts every Sept. 11 by addressing students during morning announcements.

He reads a short tribute he wrote about people killed that day, “the heroic members of Flight 93 who saved countless lives and first responders who raced up smoke-filled stairs in downtown Manhattan.”

“Many of us who were old enough to remember that day will never forget what we saw and the sadness we felt,” Suttie tells students before asking them to join him in a moment of silence.

Suttie said he thinks it’s important to continue to recognize that 9/11 was an crucial moment in American history.

“To not acknowledge it would be a mistake,” he said. “It’s important to acknowledge this horrible thing happened and honor the lives that were lost.”

Staff Writer Rachel Ohm contributed to this report.