Next Monday, about 40 teenagers between the ages of 12 and 18 will audition to join five afterschool dance troupes at the 92nd Street Y’s Harkness Dance Center: Fresh Y Crew, an all-boys hip-hop group; 92nd Street Y Tap Team; Harkness Youth Ballet; Young Master Repertory Ensemble, a modern-dance group; and the 92nd Street Y Lindyhoppers, a swing group.

In the fall, 45 students took part in the program, which is designed to give teens an opportunity to participate in a performing “company.” The swing group, the Lindyhoppers, was the largest last season, with a total of 16 male and female dancers, but each of the troupes can accommodate up to 20 dancers.

Regardless of the size of each “company,” the 70-year-old Harkness Dance Center seeks to provide a broad range of performance opportunities. Last semester, the Young Master Repertory Ensemble had only two members – and they got plenty of extra attention.

In a large, wood-floored, mirrored rehearsal space, the currently all-female 92nd Street Y Tap Team rehearsed last week as David Byrne’s rendition of “Don’t Fence Me In” filled the air. Ten teenage girls, all clad in jeans, some with ponytails, others with long hair flowing loose, tapped their way through the routine.

Vic Di Monda, their teacher, commanded: “Hands on your belt buckle, so you can relax your arms. Let’s do that again.” The girls rehearsed three steps and a turn, over and over.

Meanwhile, two boys from the Fresh Y Dance Crew waited in the lobby of the Harkness Dance Center before heading to Brooklyn for a performance. Chris Vivolo, 18, a member of Fresh Y Crew since its inception four years ago, chatted with 14-year-old Stuyvesant High School freshman Maurizio Martinelli, another dancer.

“We all have these with our name on the back,” Chris said, pulling up his York Prep polo shirt to reveal a Fresh Y Crew black T-shirt underneath. His attire was, in the words of someone in the small gathering “kind of prep meets hip-hop.” Maurizio wore blue jeans, skater shoes, and a bright red T-shirt proclaiming “TV Makes You Smarter.”

Both Chris and Maurizio study jazz dance at the Y, in addition to performing with Fresh Y Crew. The Harkness Dance Center fosters an apprenticeship program, in which senior dancers such as Chris can help teachers such as Sal Pernice, Fresh Y Crew’s director. “I was in his jazz class for about seven years,” explained Chris. “Now I assist his lower-age classes. I get to help the kids grow, dancing-wise.”

Maurizio said of Mr. Pernice, “I find he’s turned into a friend. He’s a great guy.” Maurizio was initially shy about getting into dancing. “My sister got me into this. The first day, I was hiding in the back. I was 8, maybe,” he said.

Chris had a similar experience: His sister took classes in the program before he did. “When I first came here, I was really nervous,” he said. But once he started taking Mr. Pernice’s class, he said, “I was hooked.”

Does everyone have to be fit to do this type of dancing? Chris, who has a stocky build, explained: “Everybody has their own style. Jeremy [another member of Fresh Y Crew] is very athletic. He break-dances; he flips. I’m more jazzy,” he said. Maurizio noted that Mr. Pernice frequently tells the dancers, “As long as you put energy in it, it looks good.” “That’s what we go by,” Maurizio said.

Fresh Y Crew meets Monday afternoons and the boys rehearse in street clothes. “We only wear costumes for performances,” Chris explained. He shows up in “whatever I wear to school.” The group danced at the 92nd Street Y’s 130th anniversary gala last spring. “We were the youngest group there,” said Chris. “That was awesome.” They shared the bill with celebrities such as Tony Curtis and Michael J. Fox.

Asked if he wanted to continue to pursue dancing beyond the Y’s program, Chris said, “I do. I definitely do.” Maurizio was more circumspect. “I don’t know,” he said. “I think I’ll keep it as a hobby.” He folded his arms. “I’ve always seen myself as some kind of businessman.”

The boys were happy to give an impromptu demonstration of their routines in the lobby, with just two of them present, no music, and various children and mothers sitting on couches in the waiting area, looking on. Maurizio emptied his pockets; Chris took a sip from the water fountain. Both removed their shoes and danced in white athletic socks.

As they started to dance, a youngster on one of the couches looked up. “Grandma, what is this?” she said, spellbound.

The boys weren’t surprised by the attention. Chris said the Fresh Y Crew stands out, particularly as an all-male dance group in a teenage dance scene that’s dominated by girls. “Here we come – six boys,” Chris said. What kind of response do they get from the female dancers? “‘Wow – they can dance,'” is often the reaction, he said.

Harkness Dance Center, 92nd Street Y, Lexington Avenue at 92nd Street. The next round of dance group auditions begins Monday, Jan 31. While the auditions are competitive, each of the troupes is looking to add to its ranks. The tap, swing, and hip-hop programs cost $450 for 17 weeks; the modern ensemble costs $335 for 16 weeks; and the ballet troupe costs $600 for 31 sessions. For more information, call 212-415-5552 or visit www.92y.org.