Khan Academy
Why it's useful: Study a range of subjects through lessons, explanations, and interactive practice.
First try: about 10 minutesCost: Free access
Best for
A learner who wants a structured explanation followed by practice rather than a list of links alone.
A good first step
Choose one topic, begin with a short lesson, complete the practice set, and note which concept still needs another explanation.
What to check
Course coverage and features vary by subject and audience. Check that a course level and language match the learner's needs.
Access and pricing
Check the official site for current availability, supported regions, and any programs or features that require an account.
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