The seniors in Ethan Cherin's first-hour history class at St. Paul Central High were in second grade the morning of the terrorist attacks on Sept. 11, 2001.
On that morning a decade ago, they were spread out across different classrooms. But today, their memories have the quality of a shared experience.
"I remember coming in from recess," said Frank Thompson, 18. "You could tell something was wrong the way everybody was looking at the television."
His 17-year-old classmate, Chloe Booth, recalls almost brushing the day's events off — until her mother arrived home.
"She was worried, because her brother — my uncle and aunt — live in New York City," Booth said.
Gov. Mark Dayton is encouraging all schools today to observe a moment of silence in memorial of September 11. But 10 years later, the attacks occupy an awkward spot in schools. For teachers and other adults, the anniversary triggers raw memories, and for them it might be too soon to treat the event as history.
On that fateful day, many of today's students weren't yet born. Even high school students don't recall much about what the world was like before the attacks — and many schools do not teach students much about the day, or its aftermath.
Textbooks do include information on the attacks and curriculum is available, but only a handful of states and school districts require teaching it. Minnesota's Social Studies standards, which are up for renewal, do not include 9/11.
It's a perpetual dilemma for civics teachers, said Kyle Ward, social studies instruction director at St. Cloud State University. He teaches future social studies teachers and helps schools develop curriculum.
"The more I've looked into it the more I've discovered we're not really teaching 9/11," Ward said.
A survey of history teachers a few years ago found most don't cover much past the Vietnam War, he said.
"Do we need to get to the modern day? If you're not, what's the purpose of studying history?" he asked. A huge issue we have to deal with in the world of history education is how far do we get? How much depth versus coverage?"
Ten years later, many students say they haven't learned as much in school about the terrorist attacks and their effects on the nation as they'd like to.
Booth said her family doesn't discuss it, and there rarely have been more than moments of silence at school.
"It would be nice to know to be able to really understand how this had an impact on our lives, because I still don't really understand that," she said. "I'm still kind of in the dark, just like I was when I was seven."
Cherin, her history teacher, said it's hard to teach students about 9/11, in part, because the anniversary falls around the start of school.
"It's always hard to get into what are potentially challenging issues with a group of students that you're just getting to know and they're just getting to know you," Cherin said.
But the lack of established curriculum does not mean teachers ignore the event. If anything, more will devise lessons on the attacks this year because of media attention on the 10th anniversary.
Bloomington schools will hold several activities focused on native son Tom Burnett, who died aboard Flight 93 in Pennsylvania.
At West High in Mankato, history teacher Matt Moore doesn't expect his ninth and 10th graders to recall much from the day, so they'll interview people this weekend who do.
"Monday they'll come back and share their interviews and insights and what they learned," he said. "We'll kind of try to come up with a collective understanding of how 9/11 was perceived in this community."
History teacher Adam Tillotson hasn't marked recent anniversaries at Wayzata High but will this year. Students will write diary entries from the perspective of someone directly affected by the attacks.
When he last gave students the assignment, on the first anniversary, one student wrote from the perspective of a mother onboard a hijacked plane. "As I look at my husband and say, 'I love you' I feel my baby kick for the first, and last time," the paper reads.
"The emotion that she penned was absolutely — it took your breath away," Tillotson said. "I showed it to several of my colleagues and they all welled up in tears."
Tillotson wonders what this year's students will capture, given their limited memories of 9/11.
Teachers say that as years pass and the nation's collective memory of the attacks fades, especially among school-aged students, schools won't need the excuse of the actual anniversary date to mark the event. Like all events, what happened on September 11, will one day be taught at whatever point in the school year history classes get to it.
"The balance between how much it's done as the commemoration and what's done factual history will shift," noted Emma Ryan, president of the Minnesota Council for the Social Studies.