The National Science Foundation
http://www.nsf.gov/

Volcanoes of the world:
http://vulcan.wr.usgs.gov/Volcanoes/framework.html

Volcano world:
http://volcano.und.edu/

The electronic volcano:
http://www.dartmouth.edu/~volcano/

Global Volcanism Program:
http://www.volcano.si.edu/gvp/

Educational sites:

The learning channel: http://tlc.discovery.com/tlcpages/volcano/volcano.html

Nova site with teachers guide:
http://www.pbs.org/wgbh/nova/hawaii/ and http://www.pbs.org/wgbh/nova/vesuvius/

University of Hawaii site:
http://www.soest.hawaii.edu/GG/hcv.html

Hawaii Volcanoes National Park:
http://volcano.und.nodak.edu/vwdocs/vwlessons/atg.html

http://www.geo.mtu.edu/volcanoes/

http://www.learner.org/exhibits/volcanoes/

http://www.cotf.edu/ete/modules/volcanoes/volcano.html

http://volcanoes.usgs.gov/main.html

Observatory sites:

Alaska volcano observatory:
http://www.avo.alaska.edu/

Montserrat Volcano Observatory:
http://www.geo.mtu.edu/volcanoes/
west.indies/soufriere/govt/

Long Valley Caldera:
http://quake.wr.usgs.gov/VOLCANOES/LongValley

Hawaiian Volcano Observatory:
http://hvo.wr.usgs.gov

Cascades Volcano Observatory:
http://vulcan.wr.usgs.gov/home.html

Merapi Volcano Observatory: http://www.vsi.dpe.go.id/mvohomepage.html

Mount Erebus Volcanic Observatory:
http://www.ees.nmt.edu/Geop/erebus.html

INGEOMINAS Pasto Volcano Observatory, Colombia:
http://www.univalle.edu.co/~ovp/index-e.html

French Volcano Observatories (Martinique, Guadeloupe, Réunion, Comores):
http://volcano.ipgp.jussieu.fr:8080

Volcano Observatories around the world:
http://exodus.open.ac.uk/williamg/volcobsv.html

Research sites:

http://www.soest.hawaii.edu/margins/Home.html

http://www.iavcei.org/

http://www.norvol.hi.is/index.html

http://www.vsc.washington.edu/

http://www.uhh.hawaii.edu/~csav/