There's a sweet spot between what you can do alone and what you can't do at all

Lev Vygotsky argued that learning happens best not at what a child can already do alone, nor at what's far beyond them, but in between, tasks they can finish only with a bit of guidance. He called that gap the zone of proximal development. It's now the basis for scaffolding techniques used across modern education.

— Lev Vygotsky, Mind in Society: The Development of Higher Psychological Processes — Harvard University Press, 1978 (compiled posthumously)
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