String, wind and brass players, as well as percussionists, are working through a gruelling violin concerto by Dmitry Kabalevsky.

Two doors down, about 35 string players are fine-tuning sections of Van Morrison’s hit, Moondance.

The fact musicians are rehearsing late on a weeknight isn’t surprising. The fact that these are children and youths aged 9 to 20 might be.

Tuesday night rehearsals from September though May at King’s Christian Collegiate are a way of life for members of the Halton Youth Symphony Orchestra (HYSO), and the Halton Youth Chamber Orchestra (HYCO).

Not only are these youths regularly devoting a school night to making music, they’re also coming in from places like Burlington, Milton, Mississauga, Ancaster and other parts of Oakville — in rush hour, nonetheless — to be here.

But the significant time commitment doesn’t seem to bother the students one bit.

For musicians like Robyn Obermeyer, there’s nowhere else she’d rather be.

“Music is my life,” said the 14- year-old violinist.

Robyn, who picked up the violin at age three, is the concertmaster of the HYSO. She was in the chamber orchestra for two years before advancing to the senior orchestra in 2007.

“I help tune the orchestra, make sure everyone has their music and has it practiced, and has the right fingerings and bowings,” she said when asked about her responsibilities as concertmaster. “I have to make sure everyone is prepared. I’ve learned that there is a lot of responsibility being a leader, especially of a group this big. Socially, as well, you learn to be everyone’s friend, but it’s really easy to get along with everyone here because we all have music in common.”

Robyn also plays piano, flute and sings. She studies violin privately, but says there are things you can only learn by playing in an orchestra.

“Orchestra helps with the theory aspect of music, as well as music history, because you learn the composers and the different styles,” she said. “It has been an amazing experience being able to play with such a great group of people.”

Responsibility is a major life skill students get out of the orchestra. Just ask Tyra Sweet, who serves as principal violist of the chamber orchestra.

“Lots of people might think we’re not professional because of our age, and while we are good friends and like to have fun, when it comes to music, we’re as professional as it can get,” said Sweet, 12, who has been playing violin for 10 years and viola for about five years. “We listen to the conductor, we listen to the music and we know what to practice. Being in this group also helps with dynamics and sight reading.”

Tyra has been a member of the chamber orchestra for two years. She is also a teen mentor with the Oakville Suzuki Association, as well as a participant in a program called the Young Artists Performance Academy at the Royal Conservatory of Music in Toronto.

She said one of her favourite aspects of playing in the HYCO is the music selection.

“I like playing because we do so many interesting songs,” she said. “We get to play songs we’ve heard of, like Moondance, and a lot of fun stuff.”

Jean-Paul is also working on the Telemann Viola Concerto in G Major, which she will perform with the HYCO at an upcoming concert.

“It should be exciting,” she said. “I’ve been busy practising and I’m pretty much ready.”

While there are many musical skills to be garnered from playing in such a group, it is also just plain fun, according to violinist Jean- Paul Augurusa.

The friendly 12-year-old boy said he loves being surrounded by people who are like him.

“I like the fact that a whole bunch of kids can come together and play what they know,” said Jean-Paul, who also plays piano and guitar. “It’s really cool. It’s also a good experience and is a chance to meet a lot of other new people and they are very kind. You get to know everyone.”

Jean-Paul has been with the orchestra for three years. He said he has learned many skills from playing in a group setting.

“I’ve learned sight reading and playing on tempo, because if one man’s out, then everyone else is,” he said.

While the music places demands on the students, it does the same to the conductors.

Janez Govednik, artistic director and conductor of the HYSO, is celebrating his 11th season with the group. The constant cycle of students moving on and new ones coming in keeps him coming back year after year.

“I like challenges and I am challenged because each year, at least 30 per cent of the group is gone in June to university or other places to study,” he said.

Musicians in the senior orchestra range in age from about 12 to 20, but the one thing that is constant is that they are all experienced musicians.

“Some of them are coming in with at least six or seven years of experience, while others are doing Royal Conservatory exams,” he said.

Students have a chance to grow as musicians with the wide range of repertoire placed on the music stands in front of them, Govednik said.

“We play everything from Bach and Vivaldi to music for movies, like Pirates of the Caribbean and Star Wars,” he said. “Everyone is also encouraged to perform solos with the orchestra.”

Besides musical skills, students are also gaining friends, Govednik said. He added that the HYSO is also unique, as most schools do not offer an orchestral program.

“Socializing is also a big part of the orchestra, because they aren’t just here to play,” he said. “It is a different group than one in school. In school, the band has all the same people in it, but here they are different people with artistic backgrounds.”

Both the symphony orchestra and chamber orchestra are taking the opportunity to strut their stuff at their Christmas concert, entitled Winter Solstice, this Sunday at 4 p. m. at Holy Trinity Secondary School, 2420 Sixth Line, Oakville.

Special guests will be Alexander and Nicholas Miles (clarinet/flute duet), Laura Andrew and Melissa Pettau (flute duet), and the HYSO Brass Ensemble.

“If people bring their kids, it shows them what other kids can do if they try and maybe they want to join or try a new instrument,” said Jean-Paul.

Tickets cost $15 for adults and $10 for seniors/students Tickets for this concert can be purchased by calling (905) 616-2760. For information on the HYSO or HYCO, visit www.haltonyouthsymphony.com .