YES! If your fabrics are 6-1/2" squares, you could trim them down to 5" (two sides), your other fabric (1 yard) could be white or off white, or whatever color you want to use, as long as it contrasts with the 6-1/2" fabrics.
The 1-1/2 inch you cut off from the 6-1/2" block could be sewn together and create a 1" border around the pinwheels. Then create a border of the same white or offwhite fabric and then you could choose a binding fabric that would tie everything in together. That would make a cute quilt!
don't know, though, if you will have enough 1-1/2" scraps to make that border around the pinwheels????
good luck on this and, most importantly......have fun!