Unschooling's emphasis is about the children learning, when they're ready to, whatever they are drawn to learn. It isn't about teaching. Unschooled kids learn a lot every day, but no one will have the same "curriculum". Just as different school districts get different materials and so have different lessons, unschooled kids each learn what they need to learn, different from one another. It is a natural timetable for learning, it's not a lack of learning.
Unschoolers may become fluent, easy readers at age 9, not 6 or 7. However, in the meantime, they may have honed unbelievable listening skills or visual. They have grown in the ways that are natural to them, but may not be valued in a one-size-fits-all classroom filled with 25 other same-age kids. And by the time they're 17 or 18, no one would know when they learned to read and it would not matter. What they will have missed is struggles with ideas they're not ready to learn or have no need to learn. They have soaked up the world in ways that make sense, are meaningful and will be remembered.
Do you (generic you, not you OP...)remember all of the information you were tested on in school? Do you remember the stuff on the tests you aced? No? Me either, but I wasn't unschooled. Instead I went to school and had to learn (really parrot back) things that there was no context for. So, I didn't really learn the stuff; at best, I remembered it enough for a test. Is that learning?
The premise for the OP's question is that kids need to be taught (or taught the exact same things in the same order) in order to learn. Nope. Untrue, and lots of times counterproductive. There is no one set of knowledge that everyone must have. Or have they whittled all of the majors in colleges down to one? I didn't hear about that...
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