Twenty-five years ago, as the space shuttle Challenger was preparing for liftoff, second-grade teacher Bette Chase stood by a television in her classroom at the Richard Maghakian Memorial School in Brookline, explaining to her students what was about to happen.

Chase, who several days earlier had returned from a tour of Cape Canaveral in Florida, had an insider’s perspective – Christa McAuliffe, the New Hampshire teacher chosen to make the flight, was her best friend.

“I went with a group to Florida to tour NASA, attend lectures, go on special tours before the flight, and while I was there, I got mugged,” recalled Chase, whose leg was badly twisted during the attack.

The second-grade teacher said she stayed a week, waiting while the shuttle’s flight was postponed “over and over again” and finally decided to return to New Hampshire to see her doctor about her injured leg, and to go back to her classroom.

“All the classes knew that Ms. Chase had been down there,” Chase said.

“I knew immediately that something had gone wrong and I didn’t want to tell the children, so I said, ‘I guess that’s all we need to see,’ ” Chase remembered. “I shut it off and went to the bathroom and bawled my head off.”

During the next several years while the Challenger disaster was still fresh in her students’ minds, Chase borrowed library books and used discussion to help her second-graders to appreciate what had happened.

Space studies aren’t part of the second-grade science curriculum, however, and over the years Chase found that the Challenger story was difficult for 7-year-olds to understand.

“I don’t cover space with my second-graders,” Chase said.

Not that teaching about the Challenger explosion would be easy for the teacher, no matter the age of her students.

“It comes back,” she said. “I got an e-mail asking if I would be willing to speak about it to the newspaper and boom! I was back there when it happened. It comes back full-fledged and it’s very hard to talk about.”

A quarter century after the tragedy, however, Chase said she hopes her best friend, and the other members of the Challenger crew, are remembered for their courage and contributions to science.

“I want people to remember the sciences, her bravery, and everybody else on the ship, all the members of the Challenger, ” Chase said. “They strove for something, a new understanding of the sciences. They wanted to bring more information to children by having a teacher in space.”

On Friday, Chase won’t be the only one at the Maghakian School remembering the Challenger crash as if it were yesterday.

Principal Liz Perry, then a fifth-grade teacher in Amesbury, Mass., said she hasn’t forgotten the pride and excitement she felt, knowing that a female teacher would be going into space.

“The science teacher came in and we were teaching as a team because it was such an important moment in history,” Perry said.

But what she remembers most vividly is how quickly her colleague moved to turn off the TV.

“Something terrible had just happened and we were trying to process it,” Perry recalled.

A similar confusion rose inside Room 16 at the Amherst Middle School on that day.

“There was disbelief,” said Sam Giarrusso, the seventh-grade science teacher who was watching the launch on television with his students. “It was a big event, a teacher from New Hampshire, and what had just happened? It was like 9/11. You’re watching and starting to see and you ask, ‘What’s going on? What does this mean?’ ”

Giarruso, who has taught at the Amherst Middle School for 33 years, said there was little discussion in his classroom afterwards.

“From a kid’s perspective, it’s hard to relate to,” he said.

But Giarrusso said he remembers everything. “We watched it happen,” he said.

So did Anthony DeMarco, a social studies teacher who watched the Challenger launch with seventh-graders in the Bow Middle School on Jan. 28, 1986. He said some of the children had known Christa McAuliffe when she taught there.

“It was truly devastating,” said DeMarco, who is now the Milford Middle School principal. “There was a lot of hope and excitement around the first teacher in space. It was an unbelievable situation. At first the kids said, ‘What’s going on?’ ”

As the Challenger began to break up in mid-flight, the teachers and students were hoping it was just a normal part of takeoff, but the reality soon became clear.

“Kids were crying. Teachers were crying. We tried to reassure the children, but there was total disbelief,” DeMarco said.

On Friday, his school will have a moment of silence to remember the Challenger.

Said John Roche, a veteran teacher at the Merrimack Middle School: “Just as with the Kennedy assassination, I will always remember the Challenger disaster. We had just brought our students down for their lunch that day and one of the teachers I saw in the hall told me what happened. I found an empty classroom and I cried.It seemed like such a waste to lose that crew because of an accident that could have been avoided.”

Merrimack resident Holly Cirillo, 33, was in Barbara McNutte’s third-grade class at Thortons Ferry Elementary School and about 8 years old when the Challenger exploded.

She had gathered with her classmates and children from another class, who sat on their desktops watching the TV at the front of the room. Cirillo said there was “a lot of prep time leading up to it,” the curriculum was heavy with details about New Hampshire astronaut, teacher Christa McAuliffe and space exploration.

“It was really built up with us,” she said. “I don’t remember all the details, but we learned all about space and what she (McAuliffe) was going to do up there.”

But when the shuttle exploded, the excitement changed to stunned silence and confusion.

“There was a big gasp and everybody went silent,” Cirillo said. “We had no idea what it was. Some kids thought that’s what happens, that they were losing parts of the shuttle. We were watching for a long time before the teachers shut the TV off. Everyone was stunned. No one expected that.”

Cirillo said the teachers in the classroom “didn’t know what to say” and weren’t sure how to handle a classroom of shocked third-graders. She said she remembers teachers crying, running back and forth between different classrooms and eventually trying to change the subject.

The next day at school, the students were able to ask questions and talk about what they saw. Cirillo said her parents used it as a history lesson, comparing the event to the assassination of President John F. Kennedy in 1963.

“My dad told me, ‘You’ll remember where you were the day this happened,’” she said. “It was the same type of thing. And I do remember it. I remember sitting on the top of my desk with my two friends and seeing the explosion.”

Hattie Bernstein can be reached at 673-3100, ext. 24 or hbernstein@cabinet.com. Staff writers Cameron Kittle and Kathy Cleveland contributed to this story