Khan Academy
Khan academy tops this list of free educational websites for 2 reasons.
The first is that it is completely 100% free, and the creators are committed to making it free forever. A couple of the sites on this list have premium courses, however, they all have some sort of “free” aspect.
The second reason khan academy is awesome is that it’s a blast to use. It gamifies the learning process by awarding users experience points for completing exercises. These exercises increase in difficulty similar to how levels in a video game get harder as you progress through the game.
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