When Americans mark 25 years since the 9/11 terrorist attacks on Friday, Kathleen Palladino will remember the day through the eyes of a New York City 6-year-old who did not yet understand what she was seeing.

Palladino was a kindergartner in Brooklyn when classmates suddenly began being called over the school PA system to go home.

Eventually, her mother arrived to collect Palladino and her older sister, and as they walked home, the little girl looked toward Manhattan.

“It was like a dividing line,” Palladino recently told Fox News Digital. “From the bridge backwards was just blackness.”

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The other side of the afternoon sky remained clear and blue.

“Mommy, why is the sky black?” Palladino remembers asking. “She just kept squeezing my hand, and we just kept going,” she said.

A quarter-century later, Palladino teaches nursery school at St. Patrick Catholic Academy in Bay Ridge, Brooklyn, where her 3-year-old students were born more than two decades after the attacks that shaped their teacher’s childhood.

She is one of several educators at the school whose memories of 9/11 stretch back to their own school days.

As the nation remembers Friday, they are teaching children about an event that remains deeply personal to them but that their students know only as history.

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Their principal, Kathy Curatolo, carries an even more personal connection — she watched one of the towers collapse from a school roof that morning, unaware her youngest brother, 31-year-old FDNY firefighter Robert Curatolo, was underneath it.

For Palladino’s young students, the lessons begin simply.

“I don’t go into the events of 9/11,” she said. “They are too young, and the scope of what happened is just beyond their understanding right now.”

Instead, she teaches them what they can do when someone is hurting.

“Can we clean up our toys without being asked? Can we go give them a hug?” she said. “Anything to show the ones that we love that we’re here for them.”

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For fourth-grade teacher Elizabeth Giacchino, 9/11 begins in her memory with a ringing telephone.

Giacchino was a sixth grader at Our Lady of Guadalupe School in Brooklyn when her teacher answered a call and told the class something had happened involving the Twin Towers.

“So many of my classmates around me just started screaming and crying because they had family members that were working in the city,” she said.

Outside the window, Giacchino could see smoke. Parents began arriving, but Giacchino and her older sister remained because their mother worked at the school.

“All I wanted to do was just be with my family at that time,” she said.

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Years later, after becoming a teacher herself, another memory took on new meaning. Giacchino remembered how calm her own teacher had remained while children cried around her.

“I don’t even know if she was feeling some type of way or if there was any personal situation she was going through, because all she thought about was us,” Giacchino said. “So that’s what I always make sure to do with my students too.”

Nikki Fregara, now a third-grade teacher at St. Patrick, was a high school senior when a phone call interrupted her first class of the day, history.

“I hate to tell you all this, but I’m afraid that the Twin Towers got hit,” she remembers her teacher saying.

The students went to the window.

“We saw the smoke,” Fregara said.

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She remembers crying and screaming in the hallway and students gathering in the auditorium around a small box television to watch the news. Fregara worried about her father, whose work took him to buildings around the city, and her sister and brother-in-law, who worked nearby.

Today, she steers her third-graders away from the graphic details and toward the first responders who ran toward danger.

“Helping others is so important, especially when they are in need,” Fregara said.

Her message to them is simple: “Never forget to be an everyday hero.”

For Curatolo, however, the hero she tells students about was her younger brother.

Curatolo was headed to a principals’ meeting on Sept. 11, 2001, when she heard on the radio that a plane had struck the World Trade Center. 

At the meeting, she and the other principals watched the second plane strike on TV before returning to their schools.

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Curatolo had four brothers, three firefighters and a police officer, and her mother initially called with reassuring news: all four were OK.

Curatolo turned her attention to her students and eventually went onto the school roof.

“I saw the second tower fall, not realizing that tower killed my brother,” she said.

Robert Curatolo had been an FDNY firefighter for six years and was assigned to Ladder 16 in Manhattan.

Kathy said Robert had just gotten off duty when the attacks began and headed toward the World Trade Center with two other firefighters in a police car. One survived, allowing the family to later learn some of what Robert did that morning.

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Robert began directing dazed people away from falling debris, Kathy said. When the first building collapsed, he was in a walkway between the towers. Curatolo survived and then returned to the rubble.

Kathy said her family learned that Robert pulled a man with two broken legs through the debris and into the street. When the second tower collapsed, Robert dove beneath a fire truck, she said, but it could not withstand the collapse.

People have asked Kathy why he didn’t leave after surviving once. “That’s not who he was,” she said. “That’s not how we were raised.”

Yet that is not the only Robert she wants her students to know. The youngest of eight siblings, Robert was funny, easygoing and athletic. He loved movies and traveling and was, Kathy remembers, almost always late.

“So he actually ended up at the Trade Center on time, where we’re like, the only thing you ever got to on time,” she said.

Robert had married at Disney World just three weeks before 9/11. The wedding was the last time Kathy saw him, though she spoke to him by phone the day before he died.

“I want them to know that Robert was — he was a regular kid growing up just like them,” she said.

Curatolo remembers realizing around the 10th anniversary that students increasingly had no memory of 9/11.

“These kids have no idea what I’m talking about unless they learn it from us in school or their parents who had experienced something,” she said.

Today, she said, children accustomed to smartphones and instantaneous communication are astonished to learn survivors sometimes couldn’t contact their families.

She tells them about grounded planes, postponed baseball games and packed churches and remembers that after the attacks, “people were kinder to each other.”

Twenty-five years later, Curatolo said she also wants students to understand that remembering tragedy does not mean allowing it to define a life.

“My brother is always with me, but I don’t let 9/11 define me,” she said. “You can survive a tragedy and still live a good life because the people who were lost don’t want you to stop living your life.”

Her family continues to honor Robert through a scholarship foundation, charitable work and support for Tunnel to Towers.

Kathy still counts him among the eight Curatolo siblings.

“There are eight of us,” she said. “Four live in Florida, three live on Staten Island, and one’s in heaven.”