Let's make a pinwheel and color it lots of bright pretty colors. As a matter of fact, as I sit here writing this note, the wind is really blowing outside my window. Any ribbons-leftover Christmas ribbon is perfect for this. That is the little thing that has a round head and two prongs that you press open.
People use it to put through holes they have punched to keep papers together.
Your mom or dad probably have some in their desk. Use your ruler to find the center of the square and mark it with a little spot. There should be a circle in the middle that is about one inch in diameter. Now fold every other point to the middle and staple them in place. Poke a hole in the middle with the point of your scissors or the tip of the brad.