Is not the great defect of our education today--a defect traceable through all the disquieting symptoms of trouble that I have mentioned--that although we often succeed in teaching our pupils "subjects," we fail lamentably on the whole in teaching them how to think: they learn everything, except the art of learning. It is as though we had taught a child, mechanically and by rule of thumb, to play "The Harmonious Blacksmith" upon the piano, but had never taught him the scale or how to read music; so that, having memorized "The Harmonious Blacksmith," he still had not the faintest notion how to proceed from that to tackle "The Last Rose of Summer." Why do I say, "as though"? In certain of the arts and crafts, we sometimes do precisely this--requiring a child to "express himself" in paint before we teach him how to handle the colors and the brush. There is a school of thought which believes this to be the right way to set about the job. But observe: it is not the way in which a trained craftsman will go about to teach himself a new medium. He, having learned by experience the best way to economize labor and take the thing by the right end, will start off by doodling about on an odd piece of material, in order to "give himself the feel of the tool."
The point of beginning with basic skills is one that I think people need to consider when looking at second (or third) language acquisition curricula. Because young children learn so well from immersion in a foreign language, many think that immersion will be sufficient and/or superior in teaching languages to older students and adults. But young children have shorter working memories, and when immersed in a foreign language, they actually break down what they hear into smaller chunks for themselves and learn those chunks. Older children and adults, with their increased working memories, are able to learn whole sentences and conversations, but that doesn't mean that is the best way for them to learn a language. I've learned a few languages as an adolescent and adult, and my experience was that it was more effective for me to memorize vocabulary and grammar rules and then practice using them to become competent in communicating in and reading/writing a new language, while language tapes of conversations were useful mostly just for learning pronunciation and idiomatic expressions.
Not as pertinent to the Sayers paragraph above, but something that I dislike in general is the heavy emphasis on giving students assignments where they are supposed to "express themselves". First, do we really want teachers grading a child on his/her expression of his/herself? I'd rather teachers evaluate academic and physical skills. Second, students are typically young, with limited knowledge of the world. I was quite frustrated in elementary school and beyond by creative writing assignments. I remember thinking sometime in 2nd-4th grade, "I don't know how to come up with something new. I'm just a kid! I don't know all the stuff that's been done before!" I had little to "express" when given a picture and a list of vocabulary words and told to produce a "creative" story based on the picture. Why didn't they instead say, "Write a story using these words and base it on the picture. We don't care if you're creative or as logical as Spock as long as you focus on writing as clearly and correctly as you can."? Creative expression, for those capable of it, should be its own reward, not an element of the assignment.