Udacity: https://www.udacity.com/
Udacity is a website that offers professional online courses with a focus on practical and active learning. It currently offers 36 courses spanning 5 categories: Business, Computer Science, Mathematics, Physics, and Psychology.
The courses are also grouped according to different levels: Beginner, Intermediate, and Advance.
Short quizzes, and assignments are provided after each lesson to test your understanding. You can watch the course videos online or download the archived lessons and assignments in compressed zip format.
All the courses are self-paced, which means you can complete particular lectures or assignments at your own pace.
Coursera: https://www.coursera.org/
Coursera is the biggest source of online courses, which are based on pedagogical foundations. It currently offers 621 courses in 25 categories from 108 providers – all free to join!
The courses span various categories such as Arts, Computer Science, Education, Engineering, Food & Nutrition, Humanities, Law, Mathematics, Medicine, Social Sciences, and many more.
Course materials can be downloaded in the form of lecture videos, presentations, and notes. Your marks for weekly assignments and final exam determine your eligibility for the Certificate of Completion. Coursera has also started a paid Signature Track program to provide verified certificates.
MIT: https://ocw.mit.edu/
MIT OCW is the top source of OpenCourseWare on the web. The site offers more course materials than any other website or organization, with reading materials from over 2100 courses in more than 10 top categories (with sub-categories) from over 30 departments.
The categories include Business, Energy, Engineering, Health & Medicine, Humanities, Science, Society, and more.
Although MIT OCW doesn’t offer online courses, it’s still the best source of free course materials for students as well as teachers. You can find recorded lectures and other study materials about various topics for free.
edX: https://www.edx.org/
edX brings the best online courses from top universities, including MIT, Harvard University, Berkeley University of California, University of Washington, and more. It currently offers 146 courses in over 20 subjects from more than 30 universities.
The courses span various categories such as Business, Computer Science, Environmental Science, Ethics, Food & Nutrition, History, Law, Literature, Philosophy, Science, and Statistics.
It is a not-for-profit open-source platform for students and institutions who want to transform learning through technology and pedagogical courses. edX offers self-paced courses, which means you can take the courses at your own pace. You can watch the lecture videos online.
You are required to complete all homework and assignments to get the Certificate of Mastery.
Canvas Network: https://www.canvas.net/
Canvas Network is an open online course network that offers more than 30 courses spanning various categories such as Arts, Business, Environmental Studies, History, Mathematics, Medicine, and Writing.
Course materials, assignments, final grades, and certificate availability vary according to the course and the instructor.
Open Education Consortium: https://www.oeconsortium.org/
OpenCourseWare Consortium has various open course content offered by many universities.
Just use the search function to look up any course that you’re interested in. You can browse courses by provider, language, and category.