One of the important issues here, again highlighted by Diane, is where we
situate teaching in all this. Maybe we most readily associate teaching
with interaction itself, which seems to fit the zpd better than something
like constructing an entire activity system. But, teaching obviously
is situated in many different activities, and is not just interaction with
students. And, in this different activities, the range of
sociohistorical agents at work should shift in important ways. I'm
thinking of Dewey here, and the sense of context
construction, organization, selection being at least as important as
interpersonal, ongoing engagement. While a functional systems approach
might better describe one
activity, the zpd could be more illuminating for the other.