To dance, you don’t need to watch yourself in the mirror to perfect your technique. You don’t have to know standard dance moves. You don’t even need to use your legs.

That was the first thing instructor Sequoia Carr Brown had to teach brother and sister Isaac and Tammy Lau when they began dance classes this fall at a new downtown performing arts and continuing-education school.

The siblings, who are both in their 30s, were born with a degenerative muscle condition and rely on wheelchairs to get around. In Brown’s class they warm up and stretch, learn choreography and rehearse for performances. It’s the kind of mental and physical stimulation not often available for people with disabilities in adult day-care programs.

“I never thought I would be dancing,” said Tammy Lau, who looks more like a teenager than a woman 38 years old. “It’s good I get to try something new and I get to be part of a team.

“This school is more challenging. They are doing more than just baby-sitting us.”

Former musical theater performer Kristian Lei started the Joshua Earl Tanjuakio Hegwood (JETH) Continuing Education and Performing Arts School in July; classes are held at the New Life Family Center on Nuuanu Avenue. It is named for her brother, Joshua, 33, who has cerebral palsy.

The school also offers academic classes three days a week for people with intellectual and physical disabilities at a cost of $520 per month. Separate after-school performing arts classes are open to all.

THE JETH school is the realization of Lei’s long-held dream to help her brother and others like him. It is funded by her nonprofit group Honolulu Broadway Babies, which she formed 12 years ago to put on shows with her friends and other performers to raise awareness and funds for a cause close to her heart.

Lei recalls singing to Joshua and his special-needs friends when they were growing up in Waianae, lifting their spirits. “They were elevated, and you see that they were happy,” she said. “They couldn’t smile, but you just knew that there was just this excitement in them.

“Music does really transcend beyond that physical block. … I really believe that the universal language is music.”

Lei said she started the school because she saw how her parents became discouraged by the dearth of continuing-education opportunities for their son after high school. Her brother tried adult day care but sank into boredom and despair for lack of a more structured, challenging program.

It was much the same for the Lau family. Norrin Lau said his son and daughter ended up “sitting at home doing nothing,” except for a daily swim in the pool at their Hawaii Kai home. At JETH “they get exposed to new things, and they have something to look forward to,” he said.

Isaac and Tammy Lau were born with Marinesco-Sjogren syndrome, which causes cataracts, muscle weakness and difficulty coordinating movements. Despite their physical challenges, Norrin Lau said both are artistically talented and intellectually bright.

His son said Lei’s program “gives me brain stimulation. It gives me something to think about … so I’m not just wasting my time at home. My dancing instructor, Sequoia, makes me move my muscles that I had not used before. It’s great exercise.”

DURING class the siblings started on the floor with Brown, who had them stretching muscles and doing pushups and isometric exercises to make them more aware of their bodies. That was followed by choreography and basic arm movements.

Brown said it was a challenge to get the pair to “unlearn what is viewed as traditional dance, (that) you have to have legs, you have to be able to do certain techniques. The challenge was helping them to learn and trust in their own body … let go of the ego; that’s why we don’t look at the mirrors.

“Their legs might be a little twisted or contorted,” but Brown tells them, “if you know your body, you can align it correctly and tell your story. … Your body will make this beautiful line regardless of the shape of the bone.”

She teaches them to use their wheelchairs as an extension of their bodies instead of thinking they’re simply dancing while sitting in a wheelchair. “They’re learning to lean their heads and shoulders into a turn, so it’s like, ‘Whee! I’m turning!’” Brown said.

The Laus have performed five times, accompanied by their instructor, with lithe, balletlike moves at charity events the JETH school supports. Brown said she could feel the audience holding its breath, then relaxing and appreciating what it was seeing.

After hearing the applause, “Tammy’s eyes were so big — she was so cute — and Isaac was grinning ear to ear!”

Those interested in classes at the JETH Continuing Education and Performing Arts School can attend a free graduation ceremony and performance from 6 to 7 p.m. Thursday at New Life Family Center.