One of the areas in which my thinking has developed in directions that I would not have expected, going from being a homeschooled student (in grades 6-12) to a homeschooling parent (with our oldest in grade 6) is coming to the realization that there's not actually that much that you learn in school, especially in the earlier grades.
Looking back with the perspective of an adult, there's very little content matter which I learned as a grade schooler that I now look back on and think, "That was important." Indeed, on the topics that I read about in depth as an adult, one of the main things that strikes me about most books written for young children is that they tend to be either wrong or so simplified as to be very close to wrong. History has become one of my main hobbies, but as you get deeper and deeper into a period the kind of storybook explanations of historical events that make for good children's history become hader and harder to make with any sense of honesty.
The things I learned as a student which stay with me are not knowledge, but skills, and they're the basics: Reading. Writing. Math. The instinct to "go look it up" if I don't know something.
The other thing I think stuck from that early period is an appreciation for good books -- though in the earlier grades when I was in parochial school this came much more from my family than from school. My dad, a lecturer by trade, was incredibly good at reading aloud. His narration was expressive and he provided characters with voices that remain memorable to me to this day. At any given time would have a book that he was reading aloud to us in installments at night. Some of these were classic sorts of things to read aloud to children: Treasure Island, The Hobbit, Journey to the Center of the Earth, A Christmas Carol Others were more unusual: He read us the books of Samuel and Kings from the Old Testament, which had the sort of blood-thirsty adventure which we enjoyed as kids. Other selections included Njal's Saga, Xenophon's Anabasis and Gregory of Tour's History of the Franks. Yet others were less arcane, but were not traditional children's literature. Dad was a big Trollope fan, and I remember him reading The Warden and Barchester Towers to us. In addition to all this reading aloud we were in general a very reading-centered family, and so I developed my own habits and preferences for reading as part of growing up in the environment.
Even there, though, what I gained from all that was more skills and affections, not "knowledge" in the sense of information gained. I recall incidents and impressions from the books that were read to me 20+ years ago, but mostly I remember the enjoyment of listening to my dad read to us.
As we've muddled through what works and what doesn't while homeschooling our own children, I've found this useful and comforting to recall. It would be claiming a little too much credit to say that we made a conscious decision to focus on the basics. It's more that, as various pressures have made it hard to get through everything, the things that get done are: math, reading, writing, religion, and read alouds. Yes, there's history and science and other topics, but it's more sporadic and project oriented. That will probably shift for the older kids in the next year or two, as they get old enough to start to handle something approaching real subject matter. But although nearly every conversation MrsDarwin and I have about homeschooling seems to circle back to, "Sheesh, are we doing enough? We should be doing more," I think that in the end getting the basics down is what matters.
Sure, they could be memorizing that elements or the kings of England or some such, and I'm sure that somewhere there's a Classical Homeschooling superhero of a parent who's pulling that off. But in the early grades I'm increasingly convinces that covering those basics and building in your children a love of knowledge and reading is really about all you really have to do.