sewNsew, your block is striking! Next time make your picture bigger.....need to see more details.
Also, congrats on teaching the grandsons to sew. Although my mom did most of the sewing in our house, I remember my dad sewing some stuff too. And I am the one in our house that does the sawing and hammering. A skill is a skill, the more learned the better.
I had instantly ruled out jaba's block as too complicated, but all of you are an inspiration to give it a try. It really looks good and the corners turn out so cool.