Explain it to a complete beginner

Teach the concept in plain words to someone who knows nothing about it.

Why it works

Producing an explanation from scratch is generative retrieval: you must reconstruct the idea and its connections rather than recognize them on a page. Aiming at a beginner strips away the jargon you might otherwise hide behind, so any gap in your own understanding becomes immediately visible.

How to do it

1. Pick one concept and write or say an explanation aimed at a curious 12-year-old.
2. Talk it through out loud or to a real person rather than just thinking it.
3. Note every point where you hesitate, hand-wave, or reach for a textbook phrase.

Evidence

Explaining material to others (the protégé effect) and explaining it to yourself (self-explanation) both improve comprehension and retention in controlled studies, because they force active generation rather than passive review. (rct)

The benefit comes from generating the explanation yourself; copying a clear explanation you found elsewhere does not produce the same effect.

Common mistake

Re-reading a polished explanation and feeling you could teach it, instead of actually producing one from memory where the gaps would surface.