Teach users what entropy is? That is unpossible (as Ralph Wiggins would say).
I have a friend who is clearly quite intelligent, but can't remember how to do cut and paste -- though I bet he knows more people by name than anyone I have ever known. Even a poor quality password meter probably helps password quality more than any single attempt to teach how to make good passwords. After all we have been trying to teach this as an industry for decades without much success.
The problem is that ad-hoc password strength measurement is usually pretty bad because writing a good meter is hard, although again something is usually better than nothing. Best practice would suggest reusing code from someone else, perhaps just as Dropbox did according to the article -- apparently zxcvbn. I am not claiming zxcvbn is actually good, just that the researchers referred to Dropbox favorably in this regard.