>It's tax free weekend in North Carolina. Anything related to school: books, clothing, laptops, school supplies, all are tax free. Going shopping...

Same here.

Just wondering, is there any rule as to where the parentheses go when you have three or more words, out of which the last one is a noun, but the others can be anything... why is "tax free weekend" a [tax free]+weekend, while "electric pencil sharpener" is not [electric pencil]+sharpener, but rather an electric+[pencil sharpener]. Does this really have to go case by case, or is there some logic to it?

I mean, there's semantics... we won't tax the free weekends (and there aren't any tax-free locked-up weekends anyway), and nobody wants to sharpen electric pencils (they are electric precisely because electricity is needed for the self-sharpening mechanism, right? :). I'm just waiting for a case when semantics will be proprietary... i.e. nobody but the speaker will know which grouping was intended.