This is interesting. I volunteer at a homework-help clinic for public housing kiddos. They&#x27;ve heard &quot;the answer is right but you got there the wrong way&quot; a lot. It&#x27;s frustrating to work with the kids, because they say &quot;if I do it that way, the teacher will say I&#x27;m wrong.&quot;<p>And, I basically don&#x27;t have a clue about how they&#x27;re being taught to do this stuff. Any sane person turns 2 x 15 into 2 x 16 - 2 or 10 + 10 + 5 + 5.<p>But this Common Core arithmetic is not quite sane. The intention is to teach reasoning skills, but the reality is that some curriculum-writer&#x27;s idea of reasoning skills has become codified. Grumble.<p>You&#x27;ll be missed, Dr. Minsky. So long, and thanks for all your teaching.