Learning requires several skills that are well taught through studies of nature. The first is observation, which comes naturally to a child, since he has already learned a language this way. If a child is moved too quickly into direct instruction (teachers telling you stuff, which then you parrot back to them) as the primary learning modality, the child may begin to doubt his ability to figure things out by himself. He'll believe the fallacy that things must be taught by an "expert" and in a specific order; otherwise there may be "learning gaps" (horrors!). Well, it's mostly the parents who buy into that nonsense, but attitudes are contagious, and though he couldn't elucidate why he has become a passive rather than an active learner, there's a good chance it's because he's been "taught at."
Observation is central to nature study, and it's beautiful because each person may discover something different. Children are encouraged to draw and write about what they see; if they're too young for that, telling about what they see is also valuable. And quite often they will have noticed something about the object that the adult hasn't seen yet. Natural objects have an "infinite complexity" aspect which means that there is always more to discover.
This leads to the second valuable learning skill, and that is patience--lengthening the attention span. Many things in nature move quite slowly: plants growing, flowers blooming, caterpillars creeping. Then there are those that move very quickly, so you have to develop the skill of patiently watching to get a glimpse: birds, falling stars, etc.
A third beautiful thing about nature study is that it is a short-cut to so many other fields of learning. It provides mental "hooks" to hang other pieces of information on--information about history and math and human society, along with the more formal study of chemistry, physics, anatomy and physiology, etc.
Last, nature is a great thing to become passionate about--after all, it is how we see the hand of God around us. At our house we're all big nature geeks, and we get excited by interesting rock formations or a strange bump on a tree or an unfamiliar insect. My second son taught himself to read and learned the number system all by himself at an early age because he developed a passion for birds. We have several bird field guides, and he would carry them around and look at the photographs in the front, try to read the name, look out the window trying to see that bird, then look at the page number by the picture and search the book until he found that page so that he could look at the map and see whether that bird lived in our area. Simple. Beautiful. No work on my part ;-)
