Teaching is learning are strongly connected to personality, as long as robots don't have one, they won't be able to replace even a significant fraction of teaching jobs.
If it was possible to program teaching for robots to carry it out, then there would be no concern about teaching effectiveness.
For robots to carry out teaching, it would be essential to know exactly (in thourough details) how teaching will develop, how learners will respond, how classroom can be managed. If this was known in advance, then teaching would have been much easier and teaching effectiveness would be automatic. I think......