Explain a hard concept at three depths

I want to understand a concept I've always half-understood — be a great teacher and explain it clearly at once, at different depths.

The concept I want to understand: ()
My current level: (e.g., complete beginner / some basics)
Why I want to understand it: (if any, e.g., needed for work / on an exam)

Explain at three depths in order:
1. "For an elementary schooler": explain once with the plainest analogy to build intuition first
2. "For a general person": add a correct but understandable explanation, pointing out common misconceptions
3. "For someone who wants to go deep": get into the key principles or details, with a real application example

Finally:
- Give 3 quiz questions to check whether I really understand (with answers and explanations)
- Point out which concept this is most easily confused with and how they differ

Constraints: make analogies apt, don't make wild comparisons; where you might be wrong, say you're unsure rather than bluff.