cleverfox10

The Course Challenge isn't a test that you either pass or fail. Instead, it gives you Mastery Points for that course, and if you miss 1 question, you won't level up in that skill, but you can still...

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3. need help

This is probably too late to be of any help to you, so sorry about that, but if other people have a similar question, I hope this helps them!  Here are some tips on the fastest way to finish a Khan...

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2. Study Group
3. How to quickly(but efffectively) do a Khan Academy course? I'm preparing for a upcoming math exam at the end of January.

I agree, it would be really useful when looking through other people's questions in a course or a video/article to be able to see which questions are unanswered, or to be able to "close" a question...

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2. Feature Requests and General Site Feedback
3. ‘UNANSWERED’ filter in questions tab