This carefully curated list contains links to the most useful technology classes from the best online learning sites.
All courses are linked to Class Central. Class Central is a site that lists most available online classes (in several categories) offered through online education portals like Coursera, Udemy, edX and Udacity. There's an occasional pop up that asks you to register, but you can go directly to a course from Class Central.
Courses are taught online through universities such as Stanford, Harvard, Johns Hopkins, MIT, and the University of London.
The class list is grouped into three levels - beginner, intermediate, and advanced. There are 177 beginner level courses, 372 intermediate level classes, and 133 advanced courses. All classes are free, though if a class offers a certificate and you want one, there's a fee to get it.
The education portals (Coursera, Udemy, edX, Udacity) require a free account to take classes. After you register and enroll in a course, some sites make it seem that you have to pay to take the course. Look for a small "audit" or similar type of link to take the class for free.
Sifting through the classes to find a course you want isn't easy. Courses in Class Central can be found in odd categories. For example, the 'Intro to Python for Data Science' class is listed with the 'Developing Your Musicianship' class in the Humanities category. That's where this curated list comes in, finding the good tech classes has been done already.
(h/t 4wd via Donation Coder)
You can find more Tech Treats here.