Katie Ledecky stood in front of her classmates, all 300 of them sitting, legs crossed, on the cold floor of an assembly hall.

They wore “Ledecky Team USA” shirts over their Catholic school uniforms, several with Katie’s autograph in blue marker. They chanted “Katie, Katie, Katie!” Ledecky smiled the width of a pool, rocking back and forth in the Nikes she wore in London when a gold medal was placed around her neck.

The assembly last week at Stone Ridge School of the Sacred Heart in Bethesda was in her honor, and there was a question-and-answer session.

Did she meet Ryan Lochte? Yes — he told her that she did a good job. Was she nervous during her race? No, pretty relaxed. Is the gold medal heavy to wear? Yes, but she’s getting used to it. And this: How have you managed to stay so humble?

“Just being around you guys,” Ledecky answered.

Three hundred high school girls replied, “Awwwwwwwwww.”

Ledecky, just 15, is trying to ease back into the bubbly life of a teenager after her improbable, dominating performance this summer as the U.S. team’s youngest Olympian. Her victory in the 800-meter freestyle — by four seconds, a swimming lifetime — made her instantly famous. Matt Lauer talked to her. People magazine, too. Fake Twitter accounts popped up with her name — a sure sign of celebrity in the age of social media.

Around 6 feet tall, with a lengthy swimmer’s wingspan, Ledecky sticks out in any crowd, even without a gold medal. But she is slipping back into her teenage character — a still low-on-the-totem-pole sophomore — by taking refuge in school, where her classmates have welcomed her back as the sweet, sometimes goofy, studious student they knew pre-London.

“I think everyone knows that I want to return to a normal life, and I want it to be normal for them too,” Ledecky said. “I don’t want anyone to feel uncomfortable at all.”

She showed up at Stone Ridge, which educates more than 600 girls from pre-kindergarten through 12th grade, a week early to work on campus ministry projects. She completed her summer reading: “Lord of the Flies” and “Pride and Prejudice.” (She preferred “Pride and Prejudice.”)

She turned in a paper on the very first day of English class. And when her teacher Miranda Whitmore asked students to write about their summers, Ledecky mentioned the Olympics, then focused on her brother Michael, who had just left for his freshman year at Harvard.

“It’s been really hard to say goodbye to my brother,” Whitmore said Ledecky wrote. “I’m really close to him.”

Told about Katie’s essay, Michael said: “We’re a very close family. We always have been.”

He said he thinks his sister will have no trouble picking up where she left off before the Olympics. “Katie is good at keeping everything in focus, in staying grounded,” he said. “She’s focused on the things she was focused on before she won the gold medal.”

Without the gold medal around her neck, Ledecky’s classmates say they can’t really tell the difference between Ledecky the Olympian and Ledecky the Stone Ridge girl.

“She’s very smart, and she answers a lot of questions in class,” said Allie Rock, a junior and aspiring filmmaker who made a stand-up-and-cheer video of Ledecky’s Olympic experience that was shown at the assembly. “Everyone just smiles when they see her. She’s still just a regular kid.”

Still, the path to being a regular kid again has had detours this past month as Ledecky has visited politicians to accept awards, stood in front of hundreds of people at a Bethesda ceremony honoring the city’s Olympians and had TV cameras at her house capturing tears rolling down her face when a young girl from the neighborhood dropped by to congratulate her. She’s scheduled to throw out the first pitch at the Nationals game against the Cubs on Monday.

Ledecky’s family has formed a protective cocoon around her, emphasizing getting back into a routine and helping her avoid too much hoopla. When Walter Reed National Military Medical Center officials asked her to visit wounded warriors, no media were notified. She went with her mother, Mary Gen. When a soldier who was unable to move her arms asked Ledecky if she could wear the gold medal, Ledecky gently placed it around her neck.

“She’s 15 years old,” said her mother, a former administrator at MedStar Georgetown University Hospital. “She’s the gold medal winner, but she doesn’t consider herself a hero.”

Ledecky’s mother, her father, David, a lawyer, and school officials seem to have similar strategies in dealing with what everyone acknowledges is an unusual situation — let Ledecky and her classmates take the lead. “We just want to stay close to her so she can let us know when she needs more support here and there,” her mother said.

Whitmore, Ledecky’s English teacher, said, “The students seem to have a natural sense of what she needs and how to let her just be her.”

Some kids, of course, are star-struck. “There are small children in the hallway saying that they are going to sell their hands on ebay because they touched @katieledecky’s medal,” one classmate tweeted Friday.

But for most, all the hoopla is slipping into the background of a fading summer. And when the topic does come up, it’s often to have fun with it.

Ledecky was in Whitmore’s class in the period before the assembly. Class had to be dismissed early. Whitmore, in a jokey schoolmarmish voice, said, “Okay, well we have to go to a celebration for someone.”

Ledecky’s mother said she realized school would be her daughter’s sanctuary not long after returning from London and landing at Dulles International Airport. Dozens of Ledecky’s classmates waited near baggage claim to greet her. Ledecky was strolling through the airport, and when she saw her classmates in the distance, she began running toward them.

“It made us feel good that she has a safety net with her classmates,” Mary Gen said.

Her mom sat off to the side at the school assembly, watching her daughter answer questions — an Olympian in the silhouette of a cute, effervescent teenage girl.

What was the opening ceremony like?

“It’s just like a really big party,” Ledecky said.

The girls laughed.

What was your favorite thing to do in the Olympic Village?

“Um, eat” Ledecky said.

The girls laughed.

Did she get to keep that special gray Nike jacket she wore on the podium?

“Yeah,” she said. “We all looooove swag.”

The girls laughed.

Pretty soon, Ledecky will start a grueling training schedule again, swimming laps at 4:45 a.m. to prepare for the 2016 Summer Games in Rio de Janeiro as her classmates snore. For now, though, Ledecky was just a girl telling funny stories about her crazy summer.

And then it was time for class.