Cook 2 ¼ cups of blueberries with ½ cup of maple syrup in a 2 quart heavy saucepan over medium heat, stirring occasionally, until blueberries have burst. Cool in an ice bath, stirring occasionally.
While blueberry mixture cools, beat cream with remaining maple syrup using a mixer until it holds stiff peaks.
Stir lemon juice and remaining 1 ¼ cups blueberries into cooled blueberry-maple mixture.
Spoon about 2 tablespoons of the blueberry mixture into each of 6 glasses and top with half crumble cookies and half whipped cream. Repeat layering until glasses are filled and serve immediately.