My children are "in attendance" in a learning environment every single day, even when we don't crack a single "school" book. (We never go a day without cracking some kind of book!) Sometimes their learning is facilitated by sitting down with our school materials. A good deal of math skill has been acquired in this way, for example. However, learning of a high order happens in many non-traditional ways as well. My kids know quite a lot about space, for example, even though we have never formally studied astronomy. Trips to the university planetarium and observatory, back-yard star gazing, and conversation with me and their dad has resulted in a wealth of knowledge that I dare say transcends what most 5 and 7 year olds know about the subject. They can identify numerous local birds, both by sight and call. They know about the habitats, migration, and feeding preferences of a number of local species. We've never studied ornithology, we just pay attention to the birds and to people who know interesting things about them. When the children see an unfamiliar one, they run for the guide book. I don't even have to suggest it! These are just two examples that come to mind. There are many more.
Think about something you have learned informally, yet know or do quite well. Maybe you learned to cook by watching your mother, or learned a great deal about your family's heritage through your own independent reading and research, or learned to identify the good and bad bugs and weeds in your garden, or taught yourself how to invest in the stock market. Was your learning process any less legitimate because it didn't come from a "class" or because no one sat you down and "taught" you? Of course not. On the contrary, the things you learned informally are probably some of the things you best remember and most enjoy knowing or doing.
There is certainly a place for formal teaching, especially of skills like math, reading, writing and reasoning -- the building blocks for acquiring and sharing knowledge. Both brick-and-mortar schools and home-schools can do a good job of imparting these skills. All kids experience informal learning as well, perhaps during breaks in the school day, and certainly at home. But kids these days are losing more and more of that unstructured, delight-led time. One of the strengths of homeschooling is that it allows extra time for the important casual, organic learning that comes from interest-based inquiry and free, child-directed play. It allows for an abundant mix of time alone, time with siblings, time with parents, and time with friends. My children have benefited enormously from this "extra" time, expanding their knowledge base and growing in intangible, un-testable ways. Ask a college admissions rep why they like homeschooled students, and you'll see that it's not because their heads are full of more stuff they learned while hitting the books:
“Homeschooled students, by and large, are a liberal arts college’s dream,” says Sabena Moretz-Van Namen, associate director of admission at the University of Richmond. “We want more students who think outside the box and color outside the lines. Homeschoolers often have developed into self-directed learners. Traditional high school students sometimes lack that trait.” Read the full article.If I ever have to report to the state, I'd better print up some of these, because I don't know how I could report them "absent" on any given day.