Josie Mannello doesn’t give much thought to the money she is earning this summer.

Mannello, who will be a junior at South Whidbey High School in the fall, is working as a physical therapist’s assistant at the Family Care Physical Therapy clinic at Ken’s Korner. This is her first official summer job, offered to her by clinic owner Jim Christensen, who is her sports training instructor during the school year.

Though she works only about eight hours a week, Mannello said the job is much better than the babysitting she did during past summers. She is learning as she works and is getting ready for a career of some kind.

“I kind of have my heart set on law,” she said.

A few miles up Highway 525, Brad Bilyeu is more focused on his paycheck. Two weeks into his job as stock assistant at the Frontier Industries lumberyard, Bilyeu said he has insurance and gas to buy this year if he wants to keep his Italian Lancia on the road.

He said he likes the work he is doing enough to stay with the job through the school year. Like Mannello, he’s learning a few things, though it’s about lumber and hardware rather than bones and tendons. But what is most important to him saving some money.

“Later in life, I’m doing something, like going to college,” he said.

Whatever their motivations, South Whidbey teens, like an estimated four million other teens in the nation, are filling their summer vacation days with work. Whether they work as waitpersons and buspeople at local restaurants swamped with tourists or in jobs that could one day lead to a vocation, they are out there every day, often getting out of bed early to head off to work during the few months in which they could sleep in.

Some of the work they do during the summer is crucial to employers, some of it is not. Mark Uhl, the recreation coordinator for South Whidbey Parks and Recreation District, said one of his school-age employees, 2002 South Whidbey High School graduate Jennifer Barrow, keeps a major portion of the park’s summer programs afloat.

In her fourth year of employment with the district, Barrow supervises weekly youth day camps. A camp counselor during the past three years, Barrow was the natural choice for the supervising position, Uhl said, and can have that job as long as her summers permit.

He said it would be impossible to hire an adult to do the work, since the hours are not full time and the position lasts only about three months out of the year.

“It works best to have a student,” he said. “We couldn’t run the day camps without them.”

What the actual impact of teen workers is on the local economy is hard to guess. Sharon Hart, the executive director of the Island District Economic Development Council, said this week that Whidbey Island businesses probably need temporary summer help, a fact borne out by increased sales during the summer months.

“People are spending some money,” she said.

However, she said, neither her agency nor the state’s Labor Market Analysis service keeps track of what portion of the summer workforce is made up of laborers between the ages of 14 and 19.

According to the most recent data kept by the United States Bureau of Labor Statistics, approximately one-third of all teens in the United States are employed over the course of the entire year. Those teens apparently needed the cash, since in 1999 teenagers spent approximately $105 billion of their own money.

Still, it’s not just the money that turns out South Whidbey’s young workforce every summer. And it is not a need for more help that inspires every employer to hire teens.

Jim Christensen said he hires sports medicine students out of his classes at the high school for summer jobs to give them experience and keep them in practice. Though they are a help in his Clinton and Freeland clinics, the business runs smoothly without them.

Christensen said some other South Whidbey employers also hire teens even if they do not need them to keep their businesses running from day to day.

“I think a lot of people feel an obligation,” he said.

That is not a bad thing. For Langley’s Jobline, a service that matches teens between the ages of 14 and 19 with jobs year round, all employment options are welcome. Holly Morgan, the program coordinator, said Jobline has matched 50 teens with jobs this summer. Come the start of the school year, the program will also try to find job “shadowing” opportunities for teens — unpaid positions in which teens will be able to learn about the work done by a professional in one field or another.

Also in the offing this fall through Jobline will be a food service class that will qualify teens for a food handler’s card. Morgan said earning the card will give many teen workers a leg up when it comes to getting work.

“Employers are happy because kids are informed to some degree,” she said.

In a few weeks, the teen work force will disappear as quickly as it cropped up in June. Teens will go back to school with — if they were thrifty — some money for the coming months.

By next summer, they will be ready for more. Jennifer Barrow said she will come back to South Whidbey after her freshman year at Central Washington University to work for the parks district again.

“Hopefully, I’ll be back next year,” she said.