More knowledgable peers should help me out, but the most prominent
discussion I know of that involves class is to be found in Psychology
of Art where there is a Plekhanov-style base-superstructure
discussion.
Empirical work was done by Luria and others in the late 1920's and
early 1930's, which fits into the overall scheme of the cross-cultural/
cross-historical Central Asian research, which looks at different social
categories of kids and their verbal development. Some of this may
be in old issues of "Soviet Psychology."
It is now a standard Western European/American/etc critique of vygotsky
that he did not carry out his own program of research with respect to
issues of units larger than a dyad except in comparative work of luria
et al.
mike