WINDSOR TERRACE — When Xavier High School religion teacher Stephanie Boccuzzi was in the fourth grade, an early morning recess session on Sept. 11, 2001, turned into an immediate dismissal. Back then, she had no idea why.

She later arrived at her Pennsylvania home to find her mother intently watching the news — and eventually learned that a cousin had been working in one of the World Trade Center towers. Fortunately, the cousin had escaped before the building collapsed. She also remembers then-President George W. Bush declaring war the following day.

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“As a fourth-grader, you’re kind of aware of what’s going on,” Boccuzzi, 30, recalled recently. “I think it was just a state of shock and disbelief, even from the point of view of a kid.” She remembered thinking, “How is this possible?”

These days, Boccuzzi teaches a junior ethics class at the Jesuit high school located two miles from ground zero. Now, every Sept. 11, she describes her experiences to students and discusses how theology comes into play when life-changing events happen.

For the last three years, Boccuzzi has discussed faith leaders’ responses to 9/11. She facilitates students’ reflection on their own images of God. This September has brought another opportunity.

Boccuzzi was not the only educator who reported planning to bring her own experiences into a Catholic classroom to discuss the 20th anniversary of the day the towers fell. Teachers serving in Brooklyn, Queens, and Manhattan said in interviews that they plan to incorporate personal reflections, making sure the next generation knows about one of the worst days in the history of New York City and the United States.

Across the East River from Xavier, Deacon Kevin McCormack, principal of Xaverian High School in Bay Ridge, recalled how his faculty, staff, and administration came together quickly on 9/11 to create a sense of calm and order amid the chaos and horror.

“I was an administrator back then and can tell you chapter and verse what I did the whole day,” said Deacon McCormack, noting the high school had a direct line of sight to the Battery and the World Trade Center.

“But, for the last 20 years, it slips further and further into memory and history, especially for young people.”

That’s why Xaverian continues to hold an annual Mass of Remembrance, sharing stories with younger generations of students and remembering the 23 alumni who lost their lives that day. Those alumni are honored in the high school’s outdoor memorial, featuring an eternal flame and a piece of structural steel taken from one of the fallen World Trade Center towers.

In line with the traditions, the victims’ names are announced over the school’s loudspeaker throughout the day of remembrance. Members of the Xaverian community pause between class periods for a moment of silent prayer. Some teachers and students venture outside to the memorial for additional prayer — which Deacon McCormack believes is the best way Xaverian remembers the day’s events.

Kathleen Carr, who teaches American history to juniors and seniors at St. Edmund Prep encourages students to have conversations with their parents to learn what they remember about that day.

“It’s just one of those events that, I think, everybody in New York City knows where they were,” Carr said. “I try to make the connection that these days are so important to remember because people lost their lives or gave up their lives after.”

Rita Draghi, an art teacher, and daughter of a retired NYPD Detective First Grade, explained that she pauses her classes at St. Saviour High School as six bells — consecutively marking particular tragic occurrences along the East Coast between 8:46 a.m. and 10:28 a.m. — ring.

Despite the passing of 20 years, she still remembers rushing to the high school’s library to watch a live news broadcast and trying to comfort a frightened transfer student from Ghana.

“Students attending high school now were not even born yet [when 9/11 happened],” Draghi said. “It is important to educate the upcoming [generation of] students of the significance of the day and the importance it holds in history.”

On the 10th anniversary of the tragic day, St. Saviour High School collected the names of 90 victims associated with the school, writing their names on placards. Students then carried those signs during their annual Walk-a-Thon in Prospect Park.

For the 20th anniversary, Draghi said students and teachers will watch a video about United Airlines Flight 93, which crashed near Shanksville, Pennsylvania after passengers and crew valiantly tried to regain control of the plane from hijackers. This year, placards bearing the names of St. Saviour-related victims who died on or after 9/11 will be displayed around Prospect Park as the St. Saviour’s students complete their Walk-a-Thon laps.

Closer to the scene of devastation in Manhattan, other faculty members in Xavier’s religion department will join Boccuzzi in taking classroom time to discuss 9/11 from a faith perspective. The school lost 10 alumni and dozens of family members in the 2001 attacks.

In his lesson plan for freshmen, Father James Hederman, S.J. incorporates a reflection written by Xavier alumnus Tommy Riches that talks about his brother, Jimmy — a 29-year-old firefighter who lost his life in the World Trade Center attack. Father Hederman customarily shares with his sophomore class an appreciation of firefighter Stephen Siller, along with Welles Crowther. He is better known as the “man in the red bandana.”

“Welles is a strong example of the Ignatian ideal,” Father Hederman said, noting that “he lost his life saving 18 or so others in the towers.”

Transformative experiences such as the terror and disbelief from 2001 highlight one’s connections to many influences and many lives, according to Boccuzzi — topics appropriate for religious conversation. “Theology is interdisciplinary,” she said, “so we cannot talk about faith in our personal lives without talking about the past and the world in which we live.”

“Discussing faith, doubt, God, and morality is how I use [the World Trade Center attack] to help them [the students] explore their image of God within the context of the historical memory of 9/11.”