The TeLearn dictionary and thesaurus is a useful growing resource of information giving overviews of concepts and ideas relevant to online and technology-enhanced learning. It's in wiki form so will hopefully grow further.

The entry pointed to by this bookmark gives one of the clearer definitions of Constructionism that I have read. I particularly like the succinct characterisation that constructionism is an operationalised pedagogical branch of Constructivism (that provides a general philosophy and set of ways of understanding how people learn, but that has little so say on the subject of how to go about improving learning). Terry Anderson and I had a question posed to us at our recent keynote at the Networked Learning Conference in Maastricht about why we did not include Constructionism in our list of generations of distance learning and I think this answers that question well: it is one of a fairly broad set of theories that fall under the constructivist umbrella and that help to define the second generation, but it is certainly not a generation in itself.