PBS
Pbs Learning Media: Volcanic Eruptions and Hazards
This interactive resource adapted from the National Park Service illustrates the difference between explosive and effusive volcanic eruptions, as well as the hazards that can result, including lahars, tsunamis, and lava flows.
Tramline
Virtual Field Trip: Volcanoes
In this virtual field trip find out about how volcanoes are formed and what kind of destruction can they cause. Discover how volcanoes affect our environment and where can you find active volcanoes on earth and on other planets.
US Geological Survey
Us Geological Survey: How Hawaiian Volcanoes Work
This page from the US Geological Survey has several links to pages that explain the formation of volcanoes. These links will also explain the creation of new land and other hazards.
US Geological Survey
Usgs: Volcanic Hazards, Features, and Phenomena
Site from the U.S. Geological Survey provides a brief list of volcano terminology including descriptions as well as links to major menus.