A method for creating an interactive display in which users/players can form the projection screen. The method includes providing granular display material, such as a layer of sand in a container, and storing a guide image and a display image in memory of a control system. Then, a projector is first operated to project the guide image on an upper surface of the display material. After a sculpting period or in response to a user or operator provided trigger, the method includes second operating the projector to project the display image on the upper surface which has been sculpted by the user into a 3D projection surface or screen during the first operating step. The projected guide image may include an outline of an object, and the display image may include an image element that is mapped to the location of the outlined object.