To put this poem into perspective/explain the term "Copybook Headings" please see below. 

Since I grew up in the Great White North, I swear when I was in grade school we still had a version of "copybook headings" and yes, I am old.  : ~ ) 

Published in October 1919 when the poet was 53 years old, "The Gods of the Copybook Headings" has proved enduringly popular, despite the fact that copybooks disappeared from schoolrooms in Britain and America during, or shortly after, World War 2.  A copybook was an exercise book used to practice one's handwriting in.  The pages were blank except for horizontal rulings and a printed specimen of perfect handwriting at the top.  You were supposed to copy this specimen all down the page.  The specimens were proverbs or quotations, or little commonplace hortatory or admonitory sayings�the ones in the poem illustrate the kind of thing.  These were the copybook headings.