Observe various severe weather phenomena in this image gallery from WGBH. Weather is the combination of factors -- temperature, wind, snow or rain, and sunlight and clouds -- that happen in a specific place at a specific time. Sometimes...

In this virtual field trip students learn about the formation of tornadoes. Students also visit websites where they can research various types of information about tornadoes.

This site gives a comprehensive look at volcanoes. It begins with a basic overview, and then goes in-depth. The site includes an expert's section, words to know, witness accounts, experiments, and how to prepare for a volcanic eruption...

This site tells how to be ready in case an earthquake occurs around you or your family.