http://www.umich.edu/~edpsych/Boyle/vygotsky.html
http://www.massey.ac.nz/~ALock/virtual/project2.htm
http://gwis2.circ.gwu.edu/%7Ekearsley/vygotsky.html
http://www.umich.edu/~edpsych/Boyle/vygotsky.html
http://www.ecel.uwa.edu.au/~jhippisl/Vygotsky
http://forum.swarthmore.edu/mathed/vygotsky.html
There is also a Bakhtin group:
http://www.shef.ac.uk/uni/academic/A-C/bakh/bakhtin.html
Jan Aukes
Amsterdam
The Netherlands