This week's sketch is the beginning of a piano piece. Yes, it's plain I don't play the piano very well. Nevertheless, I think this works pretty well (remember, I write with just pen and paper -- no keyboard allowed). The basic idea, which I've used before, is lines that converge and go apart. In this case, the outer voices in the right and left hands.
As always, you can use any or all of the posted Diabelli Project sketches as you wish for free. Just be sure to share the results. I'm always curious to see what direction someone else can take this material.