PITTSFIELD, Maine -&nbspIt’ s easy to tell when Bossov Ballet’ s summer students are in town: Clusters of rail-thin girls, walking with the trademark turned-out feet and ramrod-straight backs of a ballet dancer, can be seen visiting the local ice cream parlor or just getting some air at the town parks.

For 12 years, the summer students have been coming from nearly every state in the country to study under Andre Bossov, a Russian ballet master and former dancer and choreographer at the Kirov Ballet in St. Petersburg, Russia.

One of those students is Anna Marie Cowan, who first came to Pittsfield from Mississippi as a 10-year-old, and has returned for the summer intensive classes and will perform this weekend as Bossov Ballet Theater’ s Cinderella at the Waterville Opera House.

On Thursday, Bossov was putting the dancers through their final paces. He was working on last-minute costume adjustments, final stage decorations and directing the dancers to perfection.

During a run-through of the first act, bluebirds swarmed out of a fireplace while grasshoppers, gnomes, wood nymphs and snowflakes transformed Cowan, 18, from a charwoman into a princess in pink.

Watching from the audience, BBT’ s executive director, Michael Wyly, said Bossov made an exception for Cowan when he allowed her to attend the school at only 10 years old, a year early.

After coming to Maine each summer for the dance program, Cowan became a full-time Maine Central Institute student, graduating and moving on to become a professional dancer. In late August, she will join the Columbia Classical Ballet in South Carolina. She is one of a dozen BBT graduates who now perform professionally in St. Louis, Sao Paulo, Brazil, Florida, Colorado, Tucson, Ariz., Illinois, Connecticut, Oregon, Maryland and California.

But for Cowan, Maine will always be home. “Without Bossov Ballet, I wouldn’ t be anywhere,” she said Thursday, taking a break from rehearsal. “It is such an incredible program.

“It is very strict training that helps keep you on track with your goals,” Cowan said.

“When someone says ‘ Maine,’ I think ‘ home,’ ” Cowan said. “Being with Andre and all the other dancers, it’ s like being with family.”

Cowan said Bossov is a master at pinpointing a dancer’ s strengths and weaknesses and building on that. All of the lessons she learned in Pittsfield, Cowan said, she has carried with her through her professional dancing.

But returning to Maine for the summer intensive dance program is returning to the best times of her life, she said.

“Everything Andre says, I still hear from the professional directors,” she said.

Central Maine audiences are treated to a high-quality performance each summer, she said. “These summer productions are 100 percent professional,” Cowan said.

The BBT summer program is limited to 64 dancers who have to audition for a slot. The regimen is strict: Dancers are in the studio before 9 a.m. each day and don’ t leave until after 4:30 p.m.

But, Cowan said, “It was the best time of my life. I had so much fun.”

Cowan will dance one of the two nights as Cinderella, splitting the role with Cheyenne Richardson of Texas. The prince is Calder Taylor of Enfield, N.H., a graduate of Maine Central Institute’ s Class of 2005, now a professional dancer with Ballet Theatre of Maryland.

BBT will present “Cinderella” at 7 p.m. Friday and Saturday, Aug. 1-2, at the Waterville Opera House. For tickets or more information, call 873-7000.