Grolier Online-The American Presidency
http://gi.grolier.com/presidents/ea/prescont.html
Reference book articles on the Presidents.

The American Presidency-A Glorious Burden
http://americanhistory.si.edu/presidency/home.html
Short articles and a picture on each of the Presidents.

Internet Public Library-Presidents
http://www.ipl.org/ref/POTUS/
Variety of info. on Presidents -- including election results, other links, and interesting facts.  Note ** the Grolier links at this site do not work.  Use the Grolier link at the top of this page instead.

Presidents from the White House
http://www.whitehouse.gov/history/presidents/jm5.html
Articles about each President -- including inaugural addresses and pictures,  "fast facts", and links to articles on First Ladies.  Select your President within the appropriate dates from the right column.

American Presidents - Life Portraits (CSPAN)
http://www.americanpresidents.org/gallery/
For information about the Presidents, at the top of the page next to "Presidential Places", click on the down arrow to select a President.