A manufacturing tool for forming composite structures includes at least one interchangeable mold template having a plurality of incorporated part shapes, and a backbone that connects to and supports the at least one interchangeable mold template during a process of laying up prepreg composite material to form a plurality of three-dimensional structures corresponding to the plurality of incorporated part shapes. A method for simultaneous manufacture of a plurality of composite structures includes providing an interchangeable mold template having a plurality of three-dimensional part shapes, fastening the interchangeable mold template to a backbone structure, laying up prepreg material over the interchangeable mold template to form a material layer, repeating laying up prepreg material to form a plurality of material layers each having a predetermined fiber orientation, and curing the plurality of material layers on the interchangeable mold template to form a plurality of structures corresponding to the three-dimensional part shapes.