"It is with great sadness that we inform you of the passing of our dear friend and colleague," the school announced on Facebook.
"She was passionate about education, especially her work with math and history, and was deeply committed to her students, her school, and the craft of teaching. She developed deep and meaningful relationships with students, colleagues, and parents, and was highly effective in the classroom."
Annunziato died at home in Ridgefield, said the obituary.
She was born in Manhattan to Richard and Claudia Martimucci on Oct. 12, 1961. She went to New Canaan High School, where she met her husband, John, and graduated in 1979.
Annunziato on to earn a bachelor of science degree in psychology from Georgia Institute of Technology in Atlanta, and then earned her master of arts in history from Western Connecticut State University.
In her personal time, she enjoyed reading, taking her dog for walks, British television, exploring New York City and Philadelphia with her daughters, and spending time with her family, according to the obituary.
Annunziato is survived by her husband, John, of Ridgefield; her father, Richard Martimucci, of New Canaan; her daughters, Desiree and Christina; and her Labrador retriever, Rory.
The funeral will be held at St. Mark's Episcopal Church in New Canaan at 11 a.m. on Wednesday, Sept. 4 with a reception to follow.
Memorial donations are asked to St. Jude Children's Research Hospital at http://giftfunds.stjude.org/annunziatomemorial.
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