The median age in Grand Island Township, Michigan is 75.2, as per 2021 ACS 5-Year Estimates. Of the total population, 0.00% were under the age of 15, 0.00% aged 15 to 29, 46.15% aged 30 to 64, 53.85% aged 65 to 84, and 0.00% were 85 years of age and older.