We’ve been talking a lot about online education. Could the Internet help replace traditional learning? Are universities in trouble? Will employers ever take online learning seriously? Despite dropping names while answering those questions, however, we’ve yet to answer one overarching curiosity: Where can you go to even take these free, online classes? And thankfully, we now have you covered there, too, with at least eight different options no matter your age.

MIT OpenCourseWare — On April 4, 2001, former president of MIT Charles Vest officially introduced the concept of OpenCourseWare. He called the initiative “innovative,” saying, “OpenCourseWare is a natural marriage of American higher education and the capabilities of the World Wide Web.” Eleven years later, the program’s grown from 50 published courses to over 2,000, allowing people from around the globe to access syllabi, lecture notes, assignments and videos of virtually all MIT course content. Although OpenCourseWare doesn’t grant degrees or certificates, the platform did disrupt an entire industry.

Khan Academy — Founded by MIT alum Salman Khan, Khan Academy has a library of over 3,200 videos covering K-12 math, biology, chemistry and physics, as well as finance and history. Each video is designed as a “digestible chunk” — approximately 10 minutes long — and comes complete with interactive challenges, assessments and custom profile, points and badges to help measure a student’s progress.

Coursera — Coursera partners with top universities including, Princeton, Stanford, and the University of Pennsylvania, and then offers their courses online for free, for anyone in the world to take. With topics ranging from medicine and biology to computer science  and the humanities, students can watch lectures taught by university professors, learn at their own pace and then test what they’ve learned through various exercises.

Udacity — With a focus on more technical skills — software testing, artificial intelligence, web application engineering, etcetera — Udacity offers 11 courses for free. Yet, for those who’d like to certify their skills, they can do so online or in one of Udacity’s 4,500 testing centers for a fee. Udacity also offers to hand out any student’s résumé to one of their 20 partner companies at no cost.

University of the People — University of the People (UoPeople) is a tuition-free, non-profit online institution focused solely on granting people from around the world access to higher education. UoPeople has coupled the principles of e-learning and peer-to-peer learning to create undergraduate Associate and Bachelor degree programs in business administration and computer science for qualified students willing to learn, despite their financial, geographic or societal restraints. UoPeople has also partnered with Yale University for research, New York University to accept students and Hewlett-Packard for internships.

Udemy — New York Times best-selling authors, CEOs, celebrities and Ivy League professors have all taught courses on Udemy. Although every class isn’t free, plenty of them are, including Eric Reis’ Lean Startup course, Steve Blank’s Entrepreneur’s Checklist and a crash course on how to prototype web and mobile apps in 30 minutes. Udemy’s goal is to “help students make moves” at a pace that works for them.

MIT BLOSSOMS — Developed by professor Richard Larson, the director of MIT’s Center for Engineering Systems Fundamentals, MIT BLOSSOMS is an open education platform that provides math and science video lessons to high school students. The program can currently be found in classrooms here and abroad. In Saudi Arabia, alone, the BLOSSOMS team has trained 400 Saudi high school STEM teachers. And although there’s a “guest teacher” on the video, each film is designed to be watched in short, five-minute segments, allowing the in-class teacher to ask his or her students questions and run through various exercises.

edX — Early this May, Harvard and MIT announced edX, a joint partnership which will offer Harvard and MIT classes online for free. The first courses are expected to be announced later this summer and start in Fall, 2012. edX will also release its learning platform as open source software, so it can be used by other universities and organizations who opt to host the platform themselves. For those who don’t want to wait until the fall, a course in Circuits and Electronics is being offered through MITx, the seed that sparked the partnership.