I think it's hilarious that we have gotten to the point where the posts need footnotes. Next we will reproduce the Dunciad
Anyway, let's say there are 2 goals in teaching Shakespeare:
1) teaching children to appreciate Shakespeare as part of a shared culture
and
2) teaching children to analyze Shakespeare as literary text and/or performable play/script.
It seems to me that goal #1 precedes and may in fact be a prerequisite for goal #2, and that graphic novels, movies, and so forth would fall into appropriate activities in accomplishing goal #1, and which goal you're shooting for is going to depend on a number of factors-- you would, after all, approach a regular 9th grade English class with different goals than a 12th grade AP English class.
Ideally Shakespeare appreciation would start in the lower grades with things like those wonderful books for kids, festivals, and special programs that build their interest both in Shakespeare and drama--there are programs out there but they aren't available to every school or every student, more's the pity.