Textbooks vs. ??????
Well, money was tight, and few people bought the cantaloupes. But in such circumstances, no one would let them go to waste. So, for several weeks, my mother and her family ate all the cantaloupe they could hold. Not surprisingly, by the time I was old enough to hear this story, Mom didn't care much for cantaloupe.
Now, that doesn't mean that cantaloupes aren't delicious and nutricious. It jusst meant she had eaten her fill--enough, literally, to last a life time. Some of her brothers and sisters continued to enjoy cantaloupes, but not Mom.
When we present "specific content" lessons--you know, math, spelling, language, geography, science--to children, it's very similar to feeding them a diet of straight cantaloupes. You may say, "No, no, I give them several different courses each day." Sure. But how would you like it if you were served just cream style corn every morning,; followed by just green beans at noon; and just kholrabi for supper. Pretty soon, it would seem repetitious and boring.
In spite of this, we often insist on teaching children just that way. Now, I want to be plain that some children never, ever get tired of cantaloupes. They may decrease the quantity they eat, but they don't come to loathe them. In the same way, there are children who "just love" all sorts of medaevil practices like workbooks. But that's less about enjoyment, and more about the survival instinct of kids.
Real life experiences are more like stew. It may have an overarching flavor, but there are bits and pieces of many other things there. The student takes a spoonful of real life, seeking the dominant taste, but gets every thing else as well. So the kid gets the enjoyment of what he likes, and the nutrition from every element in the stew.
That's why not having a "curriculum" is an advantage. It gets kids in touch with the real world, and they "pick up" most of what they need automatically.
Many different projects through the years of preparation exposes them to many different stew recipes. Some are heavier on meat, some on carrots; some have corn, others don't. But through sampling the many flavors of reality, the end up ingesting a lot of things they wouldn't have eaten straight.
And they don't have the problem of becoming sick of something thet'a very, very good for them.