For Andy Mackie, teaching music is the key to saving the world — and himself.

When he came to West Hills Elementary School on Tuesday to teach the harmonica to more than 300 students, in his eyes, he created more than 300 more teachers who will pass their knowledge to other children.

It’s part of a dying wish for the 71-year-old Mackie, the Chimacum resident known as the “Harmonica Man” — and he’s been cheating death for about 12 years.

“Music is my medicine,” Mackie told West Hills first-graders. “You children are my medicine.”

Mackie’s mission to teach music to as many children as possible began almost 12 years ago after he underwent nine major heart surgeries. He was put on 15 different heart medications, but their side effects left him feeling despondent. One day, he threw away his medication, and instead of buying medicine, he bought harmonicas.

Since then, the Scotland native has handed harmonicas out to every child in his path and taught more than 16,000 children how to play the harmonica, guitar, violin, mandolin and banjo. He said his students have been everywhere from “American Idol” to the White House.

“Truthfully, what’s keeping me alive is what I’m doing with these kids,” Mackie said.

It’s all part of Mackie’s vision to improve the lives and the futures of the children he teaches. He told his young students at West Hills that learning how to play an instrument will help their behavior, their grades and their job prospects ­— and it will help everyone get along.

“We can have everyone playing music instead of fighting,” Mackie told them.

By the end of his half-hour sessions he taught to classes all day on Tuesday, even special education preschoolers learned how to play “Twinkle, Twinkle Little Star” on the harmonica.

West Hills teachers said that Mackie’s visit left an impression on their students.

“They really thought that he was really special,” said first grade teacher Gail Green, who allowed her students to practice their new skills when they got back to the classroom.

Green’s students were energized about their new harmonicas for the rest of the day — even the bus driver let them play on the bus, she said.

“The kids were having such a good time it was hard to be too strict with them,” she said.

Second grade teacher Julie Raymond said students still played their harmonicas in the school hallways the next day. She said her students took to heart Mackie’s lessons about how music helps people channel emotions and communicate.

“They were touched by the fact that music is a way to interact and deal with things in life,” she said.

The hundreds of new harmonicas were paid for by a $1,000 donation by Mystic Rebekah Lodge #168.

In November, Mackie’s health problems cropped up again. He suffered three heart attacks and underwent another heart surgery. He received more than 500 cards from students while in the hospital, and he taught his nurses how to play the harmonica. Mackie was prescribed six medications, but is only taking three — he doesn’t want the side effects of the medicine to keep him from doing what he loves most.

“If I can’t do what I want to do, there’s no point in being here,” he said.

In the Bremerton School District, Mackie hopes students will keep up with their new music skills, teach their siblings and friends how to play, and perform in concerts of their own. And in that way, he could get closer to his goal of reaching every child in the world.

“It’s all about giving of yourself,” he said.