Many of these schools and sites offer a large number of free courses and courseware. These links to individual classes represent only a small sampling of what they have to offer, and the sites are worth exploring further.
Access to scholarly journals:
Google Scholar: Search scholarly articles with Google.
Resource Shelf: See the results of searches performed by professional researchers, scholars, professors, and reference librarians.
Directory of Open Access Journals: Online access to scholarly and scientific journals—all free.
Rutgers Library Online: Rutgers library archives on African American history, literature, and culture.
CiteULike.com: Privately-run website where academic researchers can store online academic papers—a user-contributed web library.
Questia: Online library. Searchable access to journals and books.
University of Houston Libraries: Directory of free-access scholarly journals online.
JournalSeek: Online access to scholarly journals.
Virginia Tech Electronic Journals: Free, open-access e-journals at the Digital Library at Virginia Tech.
Easy explanations, tutorials, and touch-ups:
How Stuff Works: Easily understandable explanations of how just about everything works, from plasma converters to antibiotics.
Wikipedia: Online encyclopedia; good for quick definitions of terms and concepts, but not considered a valid reference resource for papers.
Mathcasts: Math tutorials.
The Owl at Purdue: Online MLA style guide, plus advice on writing academic and scientific research papers.
Education Online for Computer Software: Tutorials for Microsoft Word, Excel, PowerPoint, and other basic software useful in online learning.
Cliff Notes: Free online access to Cliff Notes literature summaries and analysis.
Physics Tutorials: Tutorials and explanations of basic physics concepts.
Biology Tutorials: Tutorials on a wide variety of biology subjects.
HTML Code Tutorial: Offers tutorials on HTML, applets, CSS, and other programming topics.
Learn2Type.com: Brush up on your typing skills—very useful preparation for online classes.
Webfoot.com: Beginner’s guide to effective email.
5-Minute Guide to the Internet: Good resource for those just getting started with Internet basics.
Glossary of Internet Terms: Definitions to both basic and advanced online terms and acronyms.
U.S. News Archives on the Web: News coverage of current and past events in all 50 states.
BBC Archives: News coverage on events all over the world. Good for a non-American perspective on events.
The U.S. Library of Congress: Newspaper and current periodical reading room. Links to on and offline news sources and archives.
NewsDirectory.com: Immense directory of newspaper and magazine archives, browsable by country or region.
Refdesk.com: American newspaper websites, listed by state.
Yahoo! Answers: Ask questions for other users to answer.
Answers.com: Free, searchable access to millions of published documents. You can also ask and answer questions online.
Scientific American: Bring your science questions to professional scientists.
Ask an Expert: find an expert and ask questions in a wide variety of fields.
AllExperts.com: Volunteer experts on a wide variety of subjects. The net’s oldest Q&A website.
PointAsk: Ask and give answers to users online.
Able2Know.com: Q&A forums with subject experts.
Experts Exchange: Mostly technology, computers, Internet, software and hardware experts.
Math Central Quandaries and Queries: Bring difficult math questions here for explanations.
References for specific topics:
Mayo Clinic: Database of diseases and conditions. Type in symptoms to match with diseases, or study individual conditions. Great resource for medical students.
Cornell Legal Information Institute: Comprehensive online resource on U.S. law code, Supreme Court decisions, and more.
National Human Genome Research Institute: A collection of resources on DNA science and genome research.
American Anthropological Association: Online resources for anthropology students.
ThomasNet: Online resources for industrial design and engineering students.
Erratic Impact: Resources for philosophy students.
Small Business Administration: Resources for students in on starting a new business
All Business Schools: Resources for students in business and accounting.
Firefly: Information about the disappearance of fireflies in urban and suburban areas
Public Library of Science: Open-access database of free scientific journals.
The Educator’s Reference Desk: Resources for education majors.
Social Science Research Network: Vast online library of social science research and data.
Astrophysics Data System Scanned Article Service: Scanned scholarly articles from Harvard’s astrophysics library.
Free Medical Journals: Database of important medical journals that offer free online access.
Artcyclopedia: Comprehensive online guide to all genres of visual art and artists.
Gray’s Anatomy Online: Bartleby.com’s online edition of Gray’s Anatomy. It’s a searchable database, complete with hand-drawn illustrations.
Meetup: Start or join a face-to-face group of online learners in your area.
Yahoo! Groups: Find an online gathering of like-minded online students.
Craigslist: Immense online classifieds. Advertise or find an advertisement for online students interested in starting a study group.
StudentCenter: Make connections with other college students. Mainly aimed toward a younger crowd.