Here are a couple articles about online courses available for free on the web. You get lectures, homework and tests, but no interaction with the professors and no college credit. They're great for homeschoolers, lifelong learners or students at other college who want the information. High schoolers can verify learning and possibly earn credit with CLEP, AP or SAT subject tests (although these classes are not specifically keyed to these tests, so reviewing specific study guides would also be necessary).
Internet Opens Elite College to All by AP Education writer Justin Pope
Education-Portal.com