I'd not come across this (2000) article from Vrasidas till now, more's the pity, because it is one of the clearest papers I have read on the distinction between objectivist (behaviourist/cognitivist)  and constructivist/social-constructivist approaches to teaching. It wasn't new by any means even 15 years ago, but it provides an excellent overview of the schism (both real and perceived) between objectivism and constructivism and, in many ways, presages a lot of the debate that has gone on since surrounding the strengths, weaknesses and novelty of connectivist approaches. Also contains some good practical hints about how to design learning activities.