I'll make you a deal. If you can explain why the arithmetic on the left works, you can make fun of all the arithmetic you like.

I'm both a trained mathematician, and a lightning calculator (somewhat rusty) - but I also teach basic arithmetic to people.

In the 90s they taught a mechanical procedure to multiple - one that kids mastered, but never understood.

Now calculators are everywhere. Teaching kids long division is not a good use of their time. Instead, they teach kids the *meaning* behind multiplication, division, addition, and subtraction.