Billie Mahoney danced with the best of them — and at 80, this sexy number isn't done yet

Billie sets the drum up in the back, next to another snare that belongs to her co-percussionist, Kandy Kahn. The conductor, Lindsey Williams, sports a shaved head and an oxford shirt and tie. He starts with a B-flat scale warm-up. Billie wields her drumsticks with a flourish — her left hand holds one stick like a pencil, and her right hand holds the other stick with her wrist facing down. After hitting the drum, she does a quick flick of the wrist and dramatically snaps the stick up high.

They start the rehearsal with the melodic "Sleepy Village" before trying to play the march-tempo "Dam Busters." The conductor focuses his attention elsewhere, so Billie taps a little shuffle in her purple-and-white Gitano tennis shoes.

"I bet Billie could do a Jimmy Cagney dance," calls out a guy from the brass section when they start on the patriotic "Melodies That Were Broadway." Billie responds by holding both her drumsticks in one hand high above her head, bending one leg slightly at the knee and striking a drum majorette pose.

Later that week, Billie heads to UMKC's Performing Arts Center to teach her twice-a-week class on Labanotation, a standardized system of charting dance moves. Billie first studied Labanotation in the 1950s and is now a specialist. She has contributed to a textbook on notation, and she has traveled all over the world to teach and chart it.

On that late Friday afternoon, there's a faint smell of sweaty bodies in the hallway. Billie's 20 students filter in and take off their shoes to protect the soft, synthetic floor. Clad in loose, comfortable clothes, they gracefully lower themselves to the floor before Billie takes roll call. "OK, I'm still trying to get to know you. Mackenzie?"

"She threw out her back in class this morning and had to go to the chiropractor," someone answers.

The students take out a packet. On the second page is a movement sequence set to "There's No Business Like Show Business." Labanotation consists of a series of triangles and rectangles that are set on a vertical staff. Notches and shades in the triangles and the rectangles indicate how the dancers are supposed to move.

Billie instructs the students to produce a live dance from what they see on paper. The students dutifully form a couple of haphazard rows. They start humming the song as they translate "Lf step F" on beat one and "Rf step F" on beat two. "There's No Business" turns out to be a basic side-to-side, forward-backward dance. The students giggle as some of their classmates move in the wrong direction.

Next, they try a sequence set to "Oh, What a Beautiful Morning." The notation is more difficult, and a woman in an orange hoodie becomes frustrated. "I'm just slow, Billie," she says.

"Can you see patterns and memorize them?" Billie asks.

"I'm slow. I'm not used to this," she responds. But after a couple more run-throughs, she nails it.

The students sit down on the floor again, and Billie quizzes them on the four pioneers of modern dance. She mentions that she studied under two of them at Connecticut College and Colorado College after she graduated from UKC.

"You see how connected you are?" a student says under her breath. Then she raises her voice to ask a question. "Technically, are we the next generation of pioneers? If you studied from them, and we're studying from you ... ?"

Billie deflects the question and says something about how some of the dancers who come to town to perform were her students at Juilliard. She taught for 15 years in the '70s and '80s in Juilliard's dance division and worked alongside José Limon and Alvin Ailey.

The class ends when the clock hits 5:10 p.m. The students clap and call out their thanks to Billie as they leave. A man lingers to talk.

"This changed my life," he says. Labanotation is completely new to him. He explains that he's a musician and that he missed having the notes written down.

"It changed my life, too," Billie replies.