TAMumof3, from what you say I am guessing you have little or no direct experience of home education? Most people do imagine that it looks just like school at home, with a parent acting as teacher and imparting knowledge to the child. This is the principal model of education which most of us saw throughout our own childhood, so it's no wonder we think it's the only one. I certainly thought that was how it had to be until I began exploring home education and learned otherwise.
It is possible to do school-at-home, and some home ed parents do prefer that model for part or all of their children's education. But I would say that the majority of us, particularly in the UK where there is a long history of educational freedom, don't take school-at-home as our main approach. (This is why the preferred term in Britain is "home education", rather than "homeschooling".)
At school, kids' main sources of information and understanding are their teachers and books. It's possible to augment those sources elsewhere at other times, but for 30 or so hours a week, schoolchildren's access to other educational sources is restricted.
Access to many sources is easier outside of the school walls. Home educating parents often see themselves not as teachers, but as facilitators who bring their children together with the information and skills they want to learn. That is done by taking them to the library, looking up documentaries, finding more knowledgeable people, looking up useful websites, buying books and science kits, taking them places, and enrolling them in classes.
You may find these views idealistic, but I assure you they aren't just theoretical. In the last 15 years I've met many home educating parents who themselves have a low level of formal academic attainment, whose children are being very effectively educated. They are not shut up in a cupboard with their parents 24/7 without internet access, without books, and without input from the rest of the community. For this reason, their education is not limited to what their parents know.