Sister Margaret Mary Houwen, O.P., who taught at Our Lady of Lourdes High School in Poughkeepsie, died April 21 at Community Medical Center, Toms River, N.J. She was 82. Sister Margaret Mary, formerly Sister Mary William, served in education ministries, primarily in New Jersey. In the archdiocese, she was a math and science teacher at Our Lady of Lourdes, 1961-1970. She also served as senior sister coordinator at Mount St. Mary Convent, Newburgh, 1986-1988. Born in Lindenwold, N.J., she entered the Dominican Sisters in 1941 and professed final vows in 1949. Since 1995 she had been a member of the Dominican Sisters of Hope which was formed by the merger of three Dominican congregations. She held a bachelor's degree from Villanova University and a master's from the University of Scranton, both in Pennsylvania. She is survived by two brothers, Harry and Joseph, and a sister, Anna McHenry. A Funeral Mass was offered April 25 in St. Joseph's Church in Toms River, with burial in the Dominican Sisters of Hope Cemetery in Newburgh.