NASA for middle-school students http://www.nasa.gov/audience/forstudents/5-8/features/index.html
National Geographic for Kids http://www.nationalgeographic.com/kids/
Google http://www.google.com
USGS volcano type site http://vulcan.wr.usgs.gov/Glossary/VolcanoTypes/volcano_types_quick_reference.html
National Museum of Nuclear Science http://www.nuclearmuseum.org/
periodic table link http://www.dayah.com/periodic/
Blank periodic table work sheet http://www.mccsc.edu/~jbrand/elements/BlankPeriodicTable.gif
Take a tour through Geologic Time. Geologic Time Line