John Milton Gregory wrote a book for Sunday school teachers toward the end of the 19th century that was disinterred by the folks up at Logos School. While his approach is overly scientific for my tastes and tends to be modernist in its assumptions about thinking, Gregory's book is enormously useful when we want to analyze our instruction or that of another. In it, Gregory summarizes the seven laws of teaching as follows:
A teacher must be one who KNOWS the lesson or truth to be taught.
it is not necessary that the child should be told anything about disintegration or dicotyledon, only that he should observe the wood and pith in the hazel twig, the pleasant roundness of the pebble; and by and by he will learn the bearing of the facts with which he is already familiar -- a very different thing from learning the why of facts which have never come under his notice.
It is fascinating to me how we bandy about words like 'classical,' 'education,' liberal arts,' and more, tossing them lightly into the air, taking them for granted, when if we stop to open them up, they are like treasure boxes or Faberge Eggs, full of tiny gems, rich meaning, and pictures, ideas, and a history we never realized.