So here is my entry for Challenge #126 Stencil Fun.
I didn't have any official Zentangle squares so I whipped out the ruler and measured this one to be sure it was the right size. I did it in my sketch book as you can see. My stencil was a series of heart stencils that had a circle in the middle. I didn't use the whole stencil but enough to make it basically uniform.
Since I hadn't intended to show the sketch book I took black squares (I had them on hand) and blocked the square off so that it would show better.
I thought using the stencil was super easy and left the creative part of my brain for what to put in and around the hearts and for coloring with watercolors. I had fun doing this one. I didn't want anything fancy, so I decided lines was the way to go. Sometimes plain and simple are still pleasing to me eye.