For three members of New York City Ballet’s corps de ballet, the biggest news of the winter season was delivered simply enough. When Kathryn Morgan, Savannah Lowery, and Rachel Piskin looked at the posted rehearsal schedule for George Balanchine’s “The Nutcracker,” they saw their names not grouped with the bulk of the young women under “Waltz of the Flowers,” but, rather, next to the ballet’s three most visible solo roles. On December 15, they’ll make their debuts: Ms. Morgan as the Sugarplum Fairy, Ms. Lowery as Dewdrop, and Ms. Piskin as Marzipan. But they’ll hardly be alone: The girls are the most prominent of eight young dancers making their debuts during the matinee.

That number may seem startling, but it’s illustrative of the youthful culture at NYCB and of the unique place “Nutcracker” occupies there. Company founder George Balanchine took special pride in his “baby ballerinas,” and, though NYCB has always stood out for its willingness to place girls from the corps at center stage, recent years have shown an increasing number of younger dancers, many under the age of 25, receiving the chance to dance alongside the company’s more experienced members.

With its many performances and empty slots created when principal and soloist dancers work as guest artists with other companies, the “Nutcracker” season stands as an ideal time for testing the limits of a young dancer. “Peter likes to give people chances during ‘Nutcracker’ to see what they’re made of,” the assistant to ballet master-in-chief Peter Martins, Sean Lavery, said. “It sends a message to everyone in the company, to all the young kids, that they do have this opportunity to try a solo.” But as the ballet also closes the calendar year of performances, it’s a chance to take stock of dancers who, in the previous seasons, may have danced important solo roles or seem poised for a breakthrough or a promotion. Ms. Lowery danced increasingly prominent parts to great acclaim in the past year, notably in the difficult, lengthy Sanguinic movement of “The Four Temperaments.” And Ms. Morgan seems especially ready for her star turn: In merely a year since joining the corps, she’s performed the lead roles in Christopher Wheeldon’s “Carousel: A Dance” and Mr. Martins’s new “Romeo + Juliet.”

A former star of the company and now one of its main teachers, Merrill Ashley, noted that the decision to give a young dancer debut opportunities is one that’s made in good faith, but carefully calculated. “Obviously, you have to see a certain degree of technique, of personality that makes you feel they could present something onstage, that’s a given,” she said. “You never really know until you give someone that opportunity: will they crumble or thrive under pressure? Many people don’t look good in a rehearsal but they light up onstage, and, unfortunately, vice versa is true as well.” There’s also the matter of shedding the comfortable cushion of the corps de ballet. “You can get away with a lot more in the corps!” Ms. Lowery joked. “They keep telling me about my fingers. I mean, who ever thinks about their fingers? The nitty-gritty details are sometimes overwhelming.” Ms. Piskin has perhaps the most challenging steps, including hops on point and big jumps, and she acknowledged the struggle to not overthink as she performs. “It’s this sweet little thing,” Mr. Lavery said of her role, “but you have to have strong, strong technique.”

It’s enough to make any dancer forget to simply enjoy the moment, but these girls haven’t lost sight of the fact that these parts are, for all of them, childhood dreams realized. Ms. Piskin started watching NYCB’s production as a 7-year-old student at the School of American Ballet. Ms. Morgan remembers watching company veteran Darci Kistler as Sugarplum. And Ms. Lowery is taking inspiration from both Teresa Reichlen, another tall dancer, and Kyra Nichols, the recently retired ballerina she grew up watching, whom she fondly recalls giving her pointers on her last day dancing with the company. As Ms. Ashley noted, a “Nutcracker” debut is a jumping-off point for these girls, complete with the challenges that accompany any great leap. “It’s a barometer that there’s interest in them and there are possibilities,” she said. “But it’s up to them to fulfill the promise.”