The "Happy Birthday" song isn't typical fare for an orchestra, but the Orchestra School of Central Ohio is a different sort of ensemble.

The group – with members ranging from beanie-clad teenagers to gray-haired senior citizens – recently serenaded two members in honor of their birthdays.

The relaxed atmosphere and eclectic blend of musicians are by design.

The for-profit school, which was founded in 2013 by Karen Madden, a professional musician and small-business owner, offers a chance for home-schooled students and adult amateur musicians to learn to play in a group.

"It's a great mix of younger and older musicians in different stages of ability," said violinist Marylee Bendig, 65, a Groveport resident. "And without question, Karen wants us to focus on enjoying what we're doing. That's what I enjoy about it."

Jennifer Fashian, a Delaware resident, has home-schooled her five children, all of whom have participated in the group, beginning in the orchestra's first year. Her 16-year-old triplet daughters currently are involved.

Fashian, a 49-year-old violinist, also is a member.

"It has been a really good, rich educational experience for all of us," she said. "Karen is so knowledgeable and has a passion for it."

Madden, 46, is a cellist who earned a degree in music education from Ohio State University in 1994. She played in several central Ohio orchestras and ensembles before starting the school.

The Worthington resident, who is married and has two children (Colin, 14, and Erin, 10), said she has long wanted to conduct an orchestra, but such a career move likely would have required a return to graduate school – and the best programs for such training aren't nearby.

"My options were flying off to a really good program and leaving my kids behind many days a week," Madden said, "or start my own orchestra."

The acumen she had gained from co-owning two small businesses helped her, she said. She took her time and studied the market.

She discovered a potential niche among adult amateurs who weren't members of regional ensembles, as well as home-schooled students. The decision to be a for-profit group was based on her desire not to compete with established symphonies.

"I deliberately drew a very dark line in the sand, not to be taking donor funds away from anybody else, so other orchestras didn't feel threatened," Madden said.

Jeani Stahler, director of education for the Columbus Symphony Orchestra, said she has heard of several efforts to draw home-schooled children to performance groups, "but I don't know that I've run into anything as well-organized" as Madden's group, she said.

"Karen seems very professional and dedicated," Stahler said. "She's been very supportive about bringing her students here for our Young People Concerts (performances the symphony puts on specifically for students)."

Madden conducts rehearsals from noon to 2 p.m. on Wednesdays rather than in the evenings, which allowed her to fulfill her vision of hiring professionals to serve as mentors to her students.

During the recent gathering – the practices take place at the Selby Park shelter house in Worthington – the group of 25 included about a half-dozen mentors. The helpers are paid a stipend, Madden said, comparable to what they would be paid with their professional groups.

"I view my role mostly as a trouble-shooter," said mentor Ann Dunnington, 33, a flutist and Gahanna resident who plays with the Westerville and New Albany symphonies. "I feel like a private teacher, showing the students how to do proper fingerings or maybe tricks to navigate them through tricky passages.

"Mostly, though, I feel like a cheerleader, giving them moral support."

Madden said she seeks to teach students how to play as part of an ensemble, which involves watching others, listening to the different instrument parts and learning such basics as how to mark up their music.

"These are industry standards," Madden said, "so if they want to go out in the big world and play in a professional orchestra, they need these foundations."

Elizabeth Fashian, a 16-year-old violinist, appreciates Madden's relaxed teaching style.

"I like it because we really get to learn a lot, and there's not a lot of pressure," she said. "We're allowed to make mistakes, and it's fine."

Although the group is not heavily concert-based, members occasionally present free performances, which are attended mostly by family and friends.

The school has two semesters a year, following a traditional academic calendar: January to May and September to December. The cost is $120 a semester.

Madden said she enjoys seeing inter-generational relationships develop.

During a break in the recent rehearsal, Hilliard resident Dan Thyng, 75, a bassist, stood talking with 17-year-old cellist Josiah Morrow.

"It's fun to see these kids come in and see how they improve over a period of a few years," said Thyng, one of the mentors, who plays with the Greater Columbus Community Orchestra, among other groups. "The enjoyment on their faces of playing, it's wonderful."

The group also has allowed Madden to fulfill her dream of conducting.

During a run-through of a song called, "American Landscape" at rehearsal, she gestured and cajoled, and afterward offered tips and encouragement.

"I sort of stumbled into a bed of roses," she said of the venture. "I'm so privileged to be able to stand there and wave my arms, not make a single sound, and see what this trust and collaboration create.

"It's such a joy."