Preheat oven to 375 degrees.
In a large mixing bowl, stir sugar, flour, and cinnamon into peaches.
Pour peach mixture into an unbaked pie shell.
In medium mixing bowl, mix crumb mixture by combing melted butter, 1/2 cup sugar, and 3/4 cup of flour.
Use a fork to mix crumb mixture until it becomes thick and crumbly.
Crumble mixture on top of peach mixture in unbaked pie shell.
Bake at 375 degrees for 50 to 60 minutes.
Note: If edge of crust becomes too brown, cover the edges only with foil or a pie shield.
Cool on wire cooling rack and serve warm or room temperature with vanilla ice cream or whipping cream.