http://www.chicagohistoryfair.org/research/recommended-websites-for-primary-sources-on-chicago-history.html
Chicago History resources from the Chicago Public Library:
http://www.chipublib.org/teen-subject/history-fair/
Chicago History Museum's Online Exhibitions
https://www.chicagohistory.org/exhibitions/#online
Facing Freedom (Chicago History Museum):
http://facingfreedom.org
CPS databases that support history fair topics (links are at the right-hand side of this page):
Encyclopedia of Chicago
Gale databases (especially U.S. History in Context and Research in Context)
Library of Congress
by Galileo librarian