CONCORD, N.H. (AP) – It was just as Christa McAuliffe would have wanted.

The Concord High School teacher and her six crewmates on the space shuttle Challenger get no special billing in a school lesson on space travel.

It was just as she once taught, that ordinary people make history. Except this time, she was the ordinary person and the history was a disaster 20 years ago today that wounded the school and city so deeply that the slightest touch still can bring tears.

This week, as he has done for 19 previous anniversaries, biology teacher Philip Browne taught his students about space travel, from the early Mercury missions to the current space station.

As McAuliffe did in her social studies classes, Browne kept it simple, demonstrating the size of the shuttle’s cargo bay with an illustration of it holding a Trailways bus. He showed how the parts of its solid rocket booster were stacked together like round Lego blocks, sealed with huge rubber washers called O-rings.

And he explained what could happen if those O-rings got cold and brittle, as they did on Jan. 28, 1986, allowing flames to escape and hit the shuttle’s huge fuel tank.

“A rubber O-ring failed, the flames leaked out, burned through the orange (fuel) tank, exploded the oxygen and hydrogen and the shuttle never made it into orbit,” he said.

Browne, 57, feels especially close to McAuliffe because he was one of the four other New Hampshire finalists in the national competition that eventually selected McAuliffe to be the first teacher in space.

Around each anniversary, he takes his classes to McAuliffe’s grave and the nearby planetarium built in her honor. In class, Browne calmly and expertly explained the science, but in an interview afterward, a single word about the cemetery sojourn brought him to tears: “Why?”

“I don’t want anybody to forget,” he said, taking a deep breath to fight sobs. “I don’t want anybody to forget … their bravery, their dedication. They were people who loved life. They wanted something better for the world. I don’t want them to forget.”

Each year, Concord residents struggle with how to remember and forget, some because memories of the explosion still are raw; some out of a sense of duty to McAuliffe’s husband, Steven, who still lives here; and some to maintain the cocoon the city built around him and his young children at the time.

No special ceremonies are planned by the city, though the school is exhibiting material from her odyssey and showing students a new documentary about the teacher-astronaut’s life.

Assistant Principal Bill Haubrich said the anniversary presents an annual dilemma.

“There is a legacy here. How do we promote the legacy, and not promote that particular day that was the most painful day in our school’s history?” he said.

Steven McAuliffe and children Scott and Caroline disappeared from public view after the explosion, and he has maintained his silence on anniversaries. In a rare comment, McAuliffe, now remarried and a federal judge, said he is grateful to the community.

“Our children have been taken in and protected by everyone, and so were allowed to grow up normally and without undue focus or attention, in the best of American small towns,” he wrote in an e-mail to The Associated Press. “I suspect there are not many places where that could have happened, and I know Christa would want me to express her appreciation as well for that priceless gift.”

Scott, 29, is “married to a wonderful young woman, and pursuing a career in marine resource management,” McAuliffe wrote. “Caroline is 26, still single, and pursing a career in early childhood education.

“They both are healthy, happy, great kids, and first-rate people.”

McAuliffe expressed gratitude for the public’s continuing interest in the Challenger crew.

“It is quite moving to know that so many people across the country still keep Christa, Dick (Scobee), Mike (Smith), Judy (Resnik), Ron (McNair), El (Onizuka), and Greg (Jarvis) in their thoughts and prayers. I know that they would be very thankful for the support given their families, and would urge each of us to live life to the fullest, as they did,” he wrote. “Thanks.”

Twenty years ago, the city buzzed with excitement over Christa McAuliffe, who was 37. Scott’s third-grade class even went to Florida for the launch.

Ben Provencal, 28, was one of the third-graders shivering in the VIP bleachers when Challenger exploded 73 seconds after liftoff.

He remembers the blast, the emptiness and the reluctance long afterward for teachers and friends to talk about space travel, especially when Scott was around. Now he focuses on other aspects of the trip, and on McAuliffe’s goal.

He does it as “Mr. P.,” special education assistant at Concord’s Rundlett Middle School.

“I used to say “I want to be an astronaut too,’ but now I’m so proud that I teach kids and work with kids and I can follow in the footsteps of people who were as incredible as Christa was,” Provencal said.

Provencal expects there will be other disasters, but said space exploration must continue.

“If you give up and stop what NASA does, then everything they have sacrificed for us is for naught,” Provencal said. “I think it’s a slap in their face.”

Provencal is linked forever to Challenger by a full-page photo in Newsweek. He looked tiny in his oversized baseball cap, his hands pulled into his sleeves against off the cold. His teary eyes stared at white smoke and zig-zag rocket contrails the explosion painted on the brilliant, blue sky.

Now, the 6-foot-tall wrestling, football and track coach looks at the photo and recalls his head was spinning with questions, even though he and classmates knew what had happened before their parents.

“We had been studying the space shuttle at school. We knew every second of that launch sequence and what was supposed to happen,” he said.

Former classmate Zach Fried shared binoculars with his dad to gaze at the rising shuttle. He said the tragedy helped raise questions about trust.

“I think all of us ended up with perhaps a different take on institutional confidence in what the government and what adults could tell us and promise us at the time,” said Fried, 29, a graduate student at the University of Michigan. “But I don’t think it resulted in any large amount of major skepticism. I think a lot of people had the assumption that maybe we’d all be traumatized to a degree and I think that happily, that hasn’t happened.”

Fried is studying environmental psychology, which looks at ways to increase environmentally responsible behavior. He believes his career choice, and Provencal’s, may be linked to their Challenger experience.

“Perhaps it made us into more thoughtful people, more thoughtful citizens,” he said. “It may have affected us in our tendency to want to do more socially oriented things.”

Prophetically, as McAuliffe prepared for astronaut training, she realized she was caught up in her own lesson plan – that ordinary people make history. In an interview in August 1985, she said her students were part of it, too.

“I might be a name that is chosen to be put in the history book because I’m the first of a program, but what I try to tell my students is that 20 years from now, people are going to be looking back at 1985 and wondering what teenagers were like because they are a big part of the population.”

Provencal, the 1985 third-grader, recognized the connection.

“It’s so true,” he said. “That’s exactly what she did. She made all of us part of history.”

AP-ES-01-27-06 1301EST