This video goes over 8 great spots to learn design skills (and more!) online. These are some of my favorite personal spots to pick up new skills or take refresher courses on things that I may have forgotten, so feel free to check them out and see which ones best fit your style for learning.
Also a cool one to note is edx.org which offers verified courses from some of the top colleges / universities in the world, and also lets you take the classes for totally free if the verification isn't important to you. The classes at this (and some of the other) places listed in this video go well beyond just design, so feel free to check out the entire catalog of educational opportunities.
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