Last spring, Tom Buxton was horrified when a sixth-grade student told him she thought 9/11 was an accident.

“An accident. That was it,” recalled Buxton, an English teacher at P.S. 259 in Bay Ridge.

The student’s inaccurate statement prompted him to devote an entire year of his English class to teaching students about 9/11.

Along with the 9/11 Museum, the city Department of Education created a curriculum for teachers to teach 9/11, which can be used in K-12 social studies, history or English classes.

But Buxton felt the pre-planned curriculum lacked a human element. He invited guest lecturers, like a man who lost a relative in the towers and a person who carried another in a wheelchair down 62 floors to speak to his seventh-grade class.

“For two hours, you didn’t hear a chair move,” he said.

With the help of art teacher Roma Karas, students transformed a hallway at the school into a 9/11 memorial, complete with steel and even glass salvaged from the towers. As part of the mural, students included a fireman in the pose of Michaelangelo’s statue of David.

Many of his students, toddlers when the tragedy struck, are just now reaching the age where they are able to comprehend bits and pieces of the terrorist attack.

And Buxton said he felt the need for understanding was dire.

Before last year’s project, some students said their parents told them that 9/11 was a tragedy, but didn’t elaborate.

Or, in some cases, their parents told them nothing at all.

“When I used to hear it, I just thought nothing,” Kelly Perez, 12, told Metro. “I just thought it was another story on the news.”

Now, she said, she draws hope from the anniversary. “In the end, our entire country united.”

How to talk to kids about 9/11

Dr. Mary Pulido, director of the New York Society for the Prevention of Cruelty to Children, said the disaster should be approached delicately.

“The little ones, kindergarteners down, they shouldn’t even know what 9/11 is at this point,” she said. “Eleven or 12-year-olds, they were born or one or two years, so I doubt they’ll have vivid memories of it at that age.”

Children may come home from school today wondering about Sept. 11, or perhaps have a friend with a personal connection, she said.

“Let them bring it up,” she advises. Say something like, ‘Why do you think we’re remembering the anniversary?’ or ‘What did you hear in school about Sept. 11?’”

For children, she said, “The bottom line is, they want to know they’re safe,” wondering if a terror attack will happen again or whether their parents are safe going into work.

She suggests saying something like, “There were people who did not like the United States. They wanted to do us harm, they wanted to scare us and hurt us, so they flew a plane into the building to scare everyone in New York City and the United States. Many people died that day. It was a very sad day for all of us.”

Then, she said, transition to how many people are looking out for the child. “Everyone from the president of the United States all the way down to the local fire department and police and your mom and dad are working to keep you safe.”

In their words

Can you explain what happened on 9/11 in your own words?

“Two planes hit the World Trade Center with the purpose to destroy our lives and everything. During that time thousands of firefighters across New York City and even nearby states, New Jersey and Pennsylvania, all types of people went into the World Trade Center and tried to evacuate as many people as possible … On that day many people witnessed horrible things.” Karina Paez Rojas, 13, Bensonhurst
 
“All the police and firefighters came in a hurry to the Twin Towers. Some of them died in the Battery Tunnel. Most of them sacrificed their life to save people in the Twin Towers and they even had to leave somebody behind.” Anne Feng, 14, Fort Hamilton
 
“The firefighters and the policemen had to either stay home with their loved ones and everyone that cares about them or go help people that they’ve never met and save their lives. And they chose to save people that they don’t know’s lives and they became heroes to everyone. They risked their own lives to save other people. When they ran into the building they didn’t run out to save their own lives.” Miriam Juarez, 13, Bay Ridge

What did you know about 9/11 before Mr. Buxton’s class?

“My parents never told me basically anything about it, so when I heard it I knew something happened, I just didn’t know specifically what.” Karina Paez Rojas
 
“All I knew is that it was a day of tragic events. That’s all my mother told me. When I hear it now on the news, I have a bad feeling. When I used to hear it, I just thought nothing. I just thought it was another story on the news.” Kelly Perez, 12, Bay Ridge
 
“I thought it was like a movie, two planes crashed into a tower. My mom told me it was a big deal.” Anne Feng

What does 9/11 mean to you?

“Now it means more to me because I know more about it. I learned more about it.” Jocelyn Benietez , 12, Sunset Park
 
“It is a bad day, but in the end our entire country united.” Kelly Perez
 
“I feel actually sad in a way because all the people that passed away, but glad that they did it because they got to save people and they get recognized for what they did.” Dana Stewart, 13, Bay Ridge