Mary Blanchard Lynde was an American philanthropist and social reformer, active in all of the progressive women's movements in Wisconsin. She was the co-founder of the Wisconsin Industrial School for Girls, and the first woman in Wisconsin to receive a state office appointment.

Wisconsin Industrial School for Girls was a 19th-century American reform school in Milwaukee, Wisconsin. The Wisconsin Industrial School for Girls was the only secular reformatory institution in the state where delinquent and neglected girls could make a home. The school's purpose was the prevention of crime and pauperism of unfortunate girls; and the restoration of those who had fallen into bad habits, or inherited vicious tendencies. The system of discipline and education was adapted to the condition and needs of the pupils. There were several buildings associated with the school, including the Main Building, Russell Cottage, Lynde Cottage, Cottage Annex, Merrill Model Home, Assembly Hall, Steward's Home, Steam Heating Plant and Barn