How to make a pinwheel, you ask reminiscently? Easy... 

Take a square of stiff paper or sheet of plastic (or self-adhesive hologram stuff pressed onto thinner paper!) and cut from each corner toward the center - just to about an inch from the center point. (Consider using fancy scissors - like pinking shears, or those that make other cutting designs.) Clip the points onto the middle point of the square with something like one of those metal doodads that have a button and two legs that you press apart to hold hole-punched papers together. A 4-6" square might be what you want for a tree ornament - larger for a hold-in-the-hand pinwheel! (You can also use shiny pinwheels as little tree light decorations... Make tiny slits in the shape of a cross in the centers of the squares and in the points, to slip over the base of the lights.)