These sites contain dictionaries and other assistance for defining computer terminology. Some will be more helpful than others.
http://www.sharpened.net/glossary/index.php
Great list of terms.
http://www.dynamicwebs.com.au/tutorials/comp_terms.htm
Lots of tutorials that explain how things work and what the item(s) are designed to help solve - also includes some history of the item.
http://www.carnegielibrary.org/subject/compinternet/dictionaries.html
College Website with computer and internet terms - more formal than other sites.
http://computers.dictionary.kamous.com/translator/reference.asp?sort=&start=40
List of MANY dictionaries. Some more adult than others.
http://www.computerhistory.org/
Great site with many links and lots of information about the people and the machines behind the computer age.
http://www.hitmill.com/computers/computerhx1.html
Links with many pictures showing the development of the computer.
http://www.pbs.org/nerds/timeline/
The Triumph of the Nerds - based on the popular video series from PBS. Takes a bit of time to load due to the graphics.
http://www.elsop.com/wrc/h_comput.htm
Lots of Links to Computer History Museums around the world including information about specific computer topics. Not all links may work or be allowed from school or be totally age-appropriate. If you find any that are not helpful, please send an email to the instructor via email.
http://www.maxmon.com/history.htm - interesting link list for the ages.
http://www.crowl.org/Lawrence/history/ - images of many of the developments.
http://www.cyberstreet.com/hcs/museum/chron.htm - computer timeline...