- What exactly is the shortcut?
- Why does this shortcut seem reasonable?
- We’d all agree, I think, that 2 x 6 = 26 is not a result of this kid not understanding what multiplication is. I’ve made that mistake before, and I bet that you have too. So, why is it a common mistake? What does this say about how a mind works while working on math?
[Any advice on how to tag this, CCSS-wise?]