Agnes ‘Granny’ Zhelesnick, America’s oldest schoolteacher, turns 100

Last year, we shared the story of Agnes "Granny" Zhelesnick, America's oldest working schoolteacher who, at 99, said she planned to keep working until she turned 100.

Last week, Zhelesnik celebrated her 100th birthday at the private Sunday School in North Plainfield, New Jersey. She still has no plans to retire.

On Friday, the student body sang "Happy Birthday" to Zhelesnik in the school auditorium, which had been decorated with portraits of the beloved teacher. Principal Benjamin Fox read congratulatory letters from President Barack Obama and Governor Chris Christie.

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"She is an icon in this school," Fox told the New Jersey Press Media. "Besides the fact that she feeds everyone and makes the school smell wonderful, she just makes everybody smile. They are always hugging her. It's like a family and she is the granny of our family."

"I suppose it's the children," Zhelesnik told the Star-Ledger when asked the secret to her longevity. "It's a great life watching children grow up."

She also credits her long life to a simple motto: "keep busy."

Zhelesnik, a homemaker for 60 years, started teaching sewing and cooking classes part-time at the school when she was 81, after her husband passed away. She now teaches full-time.

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"I love them. They're my best helpers. That's the only reason why I come here, is the children," Zhelesnik told CNN last year.

When asked when she'll retire, Zhelesnik joked that she will when the kids do.

"These children have to grow up to be a hundred first," she joked to a reporter during the school assembly birthday celebration.

"I am going to stay as long as I can, make them happy as good as I can. Who could get it better?"