The lineage of the Santa Claus character is of zero relevance here, unless you can produce some evidence that administrators of the school district involved in this case are themselves practitioners of that particular branch of shamanism and are intentionally ordering teachers to include multiple references to Santa Claus in their curriculums for the express purpose of leading impressionable young minds towards joining said religion.
If this turns out to be the case, I'll be happy to discuss the matter further. Otherwise, the inclusion of this wildly famous work of poetry in the lesson plan has no more religious meaning than the average algebra equation.
You tricky devil you.
The statement to which I was responding asserted an absolute, to wit, that Santa Claus has no religious content, but, in fact, Santa Claus has an enormous pre-Christian religious position.