[jrochkind1]

I mean it's a non-obvious-to-me interesting finding though that people understood "loop expressed as tail-end recursion" as easily loop expressed as loop though! Like it's not obvious to me that their semantic equivalence would be obvious to a beginner!

I don't remember finding tail-recursion easier to learn than embedded recursion -- I do recall it being very confusing for me to learn at first either way, but I can't recall exactly what was in my head then, or how it was taught to me! It was a long time ago. But I remember finding it tough to understand.

[sitkack]

I think recursion in the tail position makes sense because "you have to go somewhere", it is just another place to go. Recursion in the middle is like starting over, so they might think of it as a weird jump.

I'd love to teach kids to program, so many minds to run (ethical) metacognitive experiments on! Once you understand recursion, you never go back (and with tail recursion you don't have to). :)