DENNISON, MARY A., of Eastchester, NY, on March 22, 2010.  Mary was born in the Bronx and lived in Eastchester for 28 years, she was 63 years old.   She loved her family, friends and career.  She spent her life as an educator in NYC and retired as Principal of P.S. 105 in the Bronx.  She is survived by her husband Robert, daughters Ann (Brian) Walsh, Elizabeth (James) Flandreau and Son Robert, sisters Eileen Glassey, Noreen Joannides and brothers Kenneth, Tommy and Kevin Groh.  Also surviving are her grandchildren  Alessandra, Mikaela, William and Tessa Walsh and Grace and Lucas Flandreau.  Calling hours at the Fred H. McGrath & Son, Inc., Funeral Home, Bronxville, 2 to 5 and 7 to 9 pm Wednesday.  Mass of Christian Burial, Annunciation Church, Crestwood, on Thursday, March 25 at 11 am.