I had this realization after we found a solid preschool for my kid, after having been at one that was just ok. Same with piano lessons. There was this moment where I just went, “oh, that’s how you do it.”

Even as someone with the flexibility and time to be a part of my kids’ educational experience, I now have an enormous appreciation for what a good teacher is capable of. They’re almost always several steps ahead of me, introducing concepts I hadn’t thought to introduce, in ways I hadn’t thought of doing it.

But also like learning any skill correctly, one needs knowledge. Feedback during the practice helps a lot to make sure what's being practiced is correct.

Teaching, instructional design, curriculum development, etc., these are knowledge-based skills just like programming, but without the automatic corrective feedback that a compiler or automated test gives you.