I just read a letter from an elementary school principal that began with the phrase, "Summer is vastly approaching." It seems to me that quickly approaching is what should have been used. I Googled the phrase & found that it is very popular, but is it correct?

Well, I'm as surprised as you. I cannot find any reference that condones it, but it is cleary a term in wide use.

Try searching on: grammar + "'vastly approaching"

You will note that many people discussing grammar use the term very readily. From that, I would conclude that it is a set phrase. I may start using it myself. Every day's a school day!

You are all idiots. This is poor english, and a waste of your time debating it.

**** off, and kill yourselves.

Petro, "english" should be written with a capital E (as it derives from a proper noun), and there should be no comma before "and" because the second clause is not an independent clause.

Now, don't be a dick.