I just ran across a piece by Jim Holt (from April 2009) in the NY TIMES about memorizing poetry:
It is indeed nice to have at least a few poems up there in the noggin. (Now I have to investigate the etymology of noggin.) If you're stuck in line or in a waiting-room, for instance, it's nice to withdraw to the pantry and take a poem off the shelf.
Aside from childrens' rhymes, "Stopping By Woods . . ." (by Frost, of course) was the first poem I memorized. We were asked to memorize it in the third grade, back when Frost was something of THE national poet. It's actually a bit of a tricky poem because of that wonderful interlocking rhyme-scheme, although I didn't notice that til later. I think I liked the poem in part because there we were at 4,000 feet in the Sierra Nevada. Images about snow, the woods, and the dark--and even horses--were familiar to us. Frost's choice simply to repeat a line at the end is one of those simple but perfect moves that helps make a good poem great. It "seals" the poem, it reinforces a sense of weary duty, and it just sounds great, like a blues refrain.
Anyway, thanks to Mr. Holt for the essay.