The secret to a long and happy life is to stay busy. At least that's what 90-year-old Helen Lennstrom believes.

And judging from her youthful demeanor, she just might be on to something.

"I love to work," said Mrs. Lennstrom, a spry and cheerful woman who lives at Chestnut Grove in New Milford.

In the cozy living room of her apartment at the retirement community, Mrs. Lennstrom sits by the window, smiling, as she talks about a life that continues to be filled with meaningful activity.

"She is always on the go," said Lee Anne Gaudenzi, Chestnut Grove administrator. "She is a joy to have here and is very grateful for everything you do for her."

One of the ways Mrs. Lennstrom keeps busy is volunteering for the Thrift Mart, where she has been active since 1990.

She was recognized in 2006 for her many years of volunteer service with the Rotary Community Volunteer Award.

The treasurer for the Thrift Mart for 10 years, as well as a member of its finance board, Mrs. Lennstrom still helps out in the store every Saturday.

"Everyone loves her, especially the customers," said Pauline Lang, past president of the Thrift Mart. "She is an absolute sweetheart."

Mrs. Lennstrom is particularly proud of her work as liaison between the Thrift Mart and New Milford High School, which involved overseeing and handing out scholarships to students.

With just a little memory prompting from her youngest daughter Kristin Mulhare, Mrs. Lennstrom traces her long life back to its roots, reflecting on how she came to be the active, vital person that she still is today.

When Mrs. Lennstrom, (nee Helen Jost) was born Sept. 23, 1919.

At the time, her parents, who were both in their 40s and had children from prior marriages, did not expect to have any more children.

"My mother thought she was going through the change of life," Mrs. Lennstrom said with a laugh.

Yet she said her parents were overjoyed at her arrival and spoiled her as the couple's only child.

For the first five years of her life, she lived in New York City, until her father moved the family "to the country," which was Elmhurst, N.Y., where she spent her childhood.

While a young girl, she learned to play piano and was active at the St. James Episcopal Church, where she played the organ for children's services.

After graduating from high school in 1937, Mrs. Lennstrom attended Drake Business School for a year, learning secretarial skills she would utilize for almost 50 years.

"I can still do Gregg shorthand," related Mrs. Lennstrom, who writes down phone messages in shorthand.

Her first job was at Underwood Eliot Fisher Typewriter Company.

She was then hired at NBC, where she worked for several years in the TV engineering department, traveling to New York City by bus from her parents' home in Sunnyside, Queens, N.Y.

"It was really exciting," Mrs. Lennstrom recalled. "It was during World War II, and they had to investigate everyone's background."

The highlight of her tenure at the network occurred when she unexpectedly had to fill in as an announcer on two occasions for a weekly Thursday evening broadcast.

Mrs. Lennstrom chuckled, "I was hoping they would keep me for that, but I guess they needed me more as a secretary."

Her daughter, Mrs. Mulhare, joined in the conversation, explaining her mother has always been an outgoing, vivacious person.

On Aug. 29, 1943, Mrs. Lennstrom married Robert Lennstrom, a technical sergeant in the Army who was stationed in France and Germany during World War II.

After the war was over, Mr. and Mrs. Lennstrom settled in Levittown, N.Y., where they raised their three children, Neal, Trisha and Kristin.

True to her energetic nature, Mrs. Lennstrom supplemented her homemaking activities by typing at home and also doing market research.

She traveled to different neighborhoods, going door to door; handing out samples of various household products for people to try out, rate against other products and then report their opinions back to Mrs. Lennstrom on her next visit.

This venture allowed her to make a little extra money and also satisfied her need to interact with others, something that has always been important to her.

During the 1950s, when most mothers did not work outside the home, Mrs. Lennstrom was employed as secretary to the assistant superintendent of schools in Levittown, where she could still be close to home and her children.

When Mr. Lennstrom was transferred to PepsiCo in Purchase, N.Y. and the family moved to nearby Rye, Mrs. Lennstrom was recruited (while attending a cocktail party) to work at American Can in Greenwich, where she remained until her official retirement in 1989.

Mrs. Lennstrom moved in 1990 to New Milford to be closer to her daughter, Kristin, and it wasn't long before she was looking for something to do.

Through a friendship with Peg Kohler, Mrs. Lennstrom soon discovered a new outlet for her vigorous personality -- as a volunteer for the Thrift Mart.

Volunteering didn't seem to be enough for her, however, so Mrs. Lennstrom, who has five grandchildren and two great grandchildren, decided to return to work in 2002 because she "needed a change."

"I was just looking through the want ads one day, and I saw that WalMart was hiring greeters. I applied for the job and was hired on the spot," Mrs. Lennstrom said.

And so she became a familiar face to shoppers, working 20 hours a week at the store until 2007, when she felt like it was time to slow down.

As Mrs. Lennstrom's story arrives full circle, her enthusiasm undiminished, she said she is content at 90, spending her time lunching with friends, enjoying dinner with residents at Chestnut Grove and working at the Thrift Mart, displaying clothing and merchandise in the store.

"They call me the putter-outer. That's how I get my exercise," Mrs. Lennstrom confides.

She is still busy. And she wouldn't have it any other way.