I'd say that rote memorization and rhythm are not enough. The problem I've run across again and again teaching both children and adults is concrete versus abstract thinking. This problem is exacerbated by current pedagogical practices: the teaching of pragamtic skills rather than rhetorical and grammatrical ones. (People don't take a class in Web standards and history, but they do take classes in FrontPage 2002 or Photoshop 7.) It's not enough to make kids memorize poetry. You have to make them study it, analyze it, write it, and enjoy it.