Mini Sand Castle Building Blocks

It looks like I had a completely different take on the Sand Castle Challenge. I have a two and half year old son, and one thing that I find important is emphasizing the idea of creativity. My small Single Block design was created as the smallest building block that would give someone the ability to create something much larger. Just like a single lego. It looks so simple by itself, but with a creative mind behind it, the options are limitless. The shape used was done so that you could put the blocks together to easily create a circle. The large face is the front side and has small indents on the corners to give a seperation between blocks when placed right next to each other. However, you can make a straight wall with no issues using this shape also.
Why so small? Well we are somewhat limited being a good distance from a beach. The size here is created for all those that have small sand/water tables for their children. I am also planning on seeing if this works good for "sa