I created this project a couple of years ago and had students fill in the grid paper with solid colors to create patterns. More recently, I have been experimenting with the one inch graph paper and different designs like the one above. (I love when I can take an old lesson and add a new twist.)
To download a copy of the Shamrock Patterning Pages in three sizes -- 1 inch, 1/2 inch, and 1/4 inch -- visit this post on Artistry of Education.