One of the most common concerns brought up about unschooling is possible "gaps". If unschoolers learn only about what they're interested in, won't they have gaps in their education?
And this strikes me as coming from such a very schooly mindset: a mindset that says that schools have the answer. That everything chosen for the school curriculum is Important, and MUST be learned at some point or other for the learner to be a properly functioning member of society! It comes from a presumption that the government knows everything that's essential knowledge for every human being. And it comes from the belief that there IS one essential body of knowledge out there to be learned!
I totally disagree.
The government wants children to learn what will help the system itself, not what's good for the individual or the community. There are also much more important, to the system, anyway, lessons taught in school than what's "learned" about the "core subjects" (see John Taylor Gatto's The Six-Lesson School Teacher).
I also disagree that there are certain "core subjects" that must be learned. As far as I'm concerned, a healthy community is made up of many people with many different skills, experiences, and knowledge bases. The things that are important for each individual to learn are those important to that individual. The idea of "gaps in knowledge" at all is pretty ridiculous, actually, when everyone can agree that there is a colossal amount of information out there. No one can hope to absorb any more than a tiny fraction of the accumulated knowledge available to them, so everyone no matter what their education will have "gaps"! It's just a matter of whether the knowledge you do have is of your own choosing, knowledge that is meaningful and worthwhile to you, or whether it's chosen by someone else, and forced down your throat "for your own good".
And really, even if I did have to pick the things I think it would be truly good for everyone to learn, I'd pick things I think would be freeing, and help people move beyond our horrible system. It would look nothing like a school curriculum. I'd say that I thought everyone should know how to truly look after themselves. Have a basic knowledge of health, how to treat yourself for a variety of common ailments using natural medicines, good nutrition (REAL good nutrition, not the food guide crap issued by governments), how to find/grow/raise your own food, how to make your own shelter, how to make decisions both individually and collectively, and live in a consensual, pro-community way with those around you. I think those things are a hell of a lot more important than algebra or the capital of Oklahoma (no offense to Oklahoma. It was just the first place that popped into my head! ;-)).
The idea of there being an essential body of information is a pervasive one, sadly. Even most homeschoolers, and many unschoolers, buy into the idea of there being core subjects, even if they don't buy into the schools idea of teaching them. I used to think that way myself, and to separate what I was doing into "subjects". Hell, I still find myself doing that on occasion! But I find it more freeing to go beyond that, to stop thinking of life as having anything to do with "subjects", and to never place different activities, different types of learning or knowledge, into a hierarchy of importance based on the pervasive schooling mindset of our society. To try instead to let myself gravitate toward the things that simply feel best, feel the most important, empowering, and good to me, whether or not those things are considered important by the rest of the world!