NORTH PLAINFIELD - America's oldest working school teacher celebrated her 100th birthday Friday.

Agnes Zhelesnik, known as "Granny," rang in the big birthday surrounded by friends.

She joined the Sundance School in North Plainfield at age 81 as a home economics teacher, following a lifetime as a homemaker.

"I'm happy doing what I'm doing," she says. "I'm thankful for all my friends that are here."

Students honored her with a special tribute performance of "The Little Mermaid."

For extended video of Zhelesnik's 100th birthday celebration, watch the clip to the left or click News 12 Extra on Optimum TV channel 612.