Constructivism and related links: http://www.emtech.net/links/construc.htm

Social Constructivism and the World Wide Web: A Paradigm for Learning: http://www.curtin.edu.au/conference/ascilite97/papers/Mcmahon/Mcmahon.html

Constructing Language at MundoHispano by Cathy Hall: http://www.angelfire.com/ma/CasaDax/MHpaper.html

Construction of knowledge as the basis of foreign language learning by Bernd Rüschoff:
http://www.uni-essen.de/anglistik/bernd/construction.htm

Project-based Learning: http://www.iste.org/research/roadahead/pbl.html

WebQuest Page at San Diego State University: http://edweb.sdsu.edu/webquest/webquest.html

Examples:

DAAD Project University of Illinois: http://deil.lang.uiuc.edu/class.pages/DAAD.html

Examples of constructivist projects: http://www.humnet.ucla.edu/humnet/teslal/technology/TA/projects.html