Cream butter with sugars; add egg, vanilla. Cream until light and fluffy. Sift together flour, baking powder, soda, salt. Stir into creamed mixture. Stir in cereal and coconut. Shape into 3/4 inch balls, place 2 1/2 inches apart on ungreased cookie sheet. Bake at 350 degrees about 10 minutes or until lightly browned. Cool slightly, remove from pan. Cool on rack. Makes 5 dozen cookies.