BRIGHTON, Mass. – Stepping into the classroom at the Oak Square YMCA in Brighton, Simon Shnapir looked like a giant descending on a land of mere mortals.

“Olympians, Olympians are here,” one little boy shouted as the 6-foot-4-inch figure skater entered the room.

Shnapir didn’t bother correcting the boy by explaining that he and his pairs figure skating partner, Marissa Castelli, are not quite Olympians but Olympic hopefuls.

Castelli (who said she reaches all of 5-4 on her skates) arrived a bit more discretely a few moments later as she stood only a head above some of the children.

She did introduce herself and Shnapir as "Olympic hopefuls" during the United States Olympic Committee’s Team for Tomorrow program.

“What’s hopefuls?” one boy asked the 23-year-old skater.

“Hopeful is we’re hoping to go to the Olympics,” Castelli explained in her best Mr. Rogers-like tone.

But while they are currently only hopefuls for the 2014 Olympic Winter Games in Sochi, there will be high Olympic hopes for the defending national champions going into the 2014 Prudential U.S. Figure Skating Championships Jan. 5-12 at the TD Garden in Boston. The 2014 U.S. Olympic Team will be named at the end of the national championships.

“We’ll probably know in a few weeks,” Shnapir, 26, told the children of their Olympic status, "we have a competition that selects the team here in Boston. It’s going to be a few weeks here at the Garden. And it will be on TV.”

The Dec. 20 event was Castelli and Shnapir’s first Team for Tomorrow event, which is part of their duties as athlete ambassadors for the USOC’s humanitarian program.

“We were lucky to be among the select few [athlete ambassadors] to go out into the community to really help out and show what we do as a sport and try to talk to kids and encourage them to stay active," Castelli said.

"It’s been a blast so far.”

The USOC launched Team for Tomorrow in 2008 to provide a vehicle through which U.S. athletes can offer their assistance and support to those in need around the world, as well as a means to continue spreading the Olympic values of excellence, friendship and respect.

Through this initiative, U.S. athletes offer assistance and support in the form of donations, volunteerism, disaster recovery support, advocacy and other contributions to communities.

Castelli and Shnapir shared their own stories before taking the children through some warm up exercises and jumps. Then they cleared space in the room so Shnapir could hoist Castelli high above his head for a series of tricks and twirls that dazzled the children.

The event was convenient for Castelli and Shnapir, who are not only from Cranston, R.I., and Sudbury, Mass., respectfully, but also train at the Skating Club of Boston — the third oldest club in the country that was home to Olympic champions Dick Button and Tenley Albright and has produced numerous national and international medalists.

At the 2013 nationals, Castelli and Shnapir became the first pairs skaters from the Skating Club of Boston to win the national title since 1961, the same year the entire U.S. Figure Skating team (including five members from New England) was killed on a plane crash en route to the world championships in Prague.

“That was just a great moment for us to bring home another gold medal to our club,” Castelli said. “We skate there every day; we look up at those banners of such American legends and icons it’s great now to be part of that and always have our name there.”

In April, Castelli and Shnapir also helped Team USA win the World Team Trophy event in Tokyo, only to fly home on the day of the Boston Marathon bombing. Castelli also had planned to take a train to New York that day before leaving for a Jamaican vacation with her boyfriend.

They both grew up attending the marathon.

“It was just so crazy that this happened,” Castelli said, “and that the marathon … It’s part of this city the marathon and you never thought something like this could be, not destroyed, but attacked.”

“It’s such a staple of our city,” Shnapir added. “I used to watch with my grandfather. I used to go every year for probably 10 years or more and watch on [Commonwealth Avenue]. … A couple times I went down to the finish line. And to think that’s exactly where it happened, that was hard.

"I mean we landed and we felt like we were so detached from it even though we wanted to be there and comforted our friends and family and make sure everyone was OK. Luckily, neither of us knew anyone in the area that was hurt but it was hard.”

Castelli and Shnapir hope to bring something positive to the city when they compete at the national championships in Boston. One of the biggest positives of having nationals in their city is that they won’t have to travel far.

“The no traveling part makes a big difference with all the trips we’ve taken lately,” Shnapir said. “It’s going to be great to have so many of our fans and all of our family who don’t have to travel. It’s going to be pretty special skating at the Garden. We’ve gotten a couple chances to skate there and practice there just to get a feel for it and it already feels a little different than any other arena that we’ve competed in.

“The past month I’ve been to the Garden probably three times for Bruins and Celtics games. It’s going to be cool being on the other side of the boards.”

While Castelli said she expects to have more than 50 friends and family in their corner during the championships, Shnapir joked that he doesn’t even know 50 people.

“We have a small family,” said Shnapir, who moved to Massachusetts from Moscow as a toddler, “but I’m sure I’ll have at least 10 people, which doesn’t seem like a lot but we have a small family.”

Both said having so many friends and family won’t make the competition anymore stressful than it already is.

“It will be more of a boost,” Castelli said. “I’m pretty sure we’ll be nervous enough.”

Aside from their friends and family attending the championships, some of the children from the Team for Tomorrow event might also be there to cheer for Castelli and Shnapir.

That’s because Castelli and Shnapir also handed out tickets to the national championships.

“You guys can come see us OK, and you can see skating live,” Castelli said.

Before the event ended, one little girl asked if their first time in the Olympic Winter Games was scary. Once again, the gentle but giant skater did not correct the small child.

“That’s a great question,” he said. “I have to make sure I kept her safe and it’s a great way for us to build trust in each other and people and develop to trust each other and other people and that’s something that is important to us as athletes and as people.

“We’ve really come to appreciate that. So hopefully you guys can take some of that away with you today.”

Justin A. Rice covers Boston Public Schools athletics for Boston.com. He is a freelance contributor to TeamUSA.org on behalf of Red Line Editorial, Inc.