This variation uses half-square triangles in the corner squares instead of squares. If you want to make the classic sawtooth star, I have a tutorial for that too.

Nine-patch blocks can also be a compilation of smaller quilting units like the 4 patch or half square triangles. You can see an example of this with my Jacob's Ladder quilt block.

Nancy shows how to arrange simple half-square triangles into beautiful row-by-row designs.