Grammatical responses to "How are you?" and "How ya doin'?"

A friend found herself managing a debate among high school students about the proper response to the everyday pleasantries, "How are you?" and "How are you doing?"

She writes:
Some students believe the proper answer is, "I am well," while others believe that "I am good" is correct.
One student made life more difficult by answering, "I am doing well." He chose "well" because the question uses the interrogative "how," which he believes calls for an adverb and thus he believes "well" is the proper response. In fact, his use of the verb "doing" may change the question completely. Oth ers believe that the response needs a predicate adjective and therefore "good" is proper.
The students' question is two-fold: 1. Is the correct response to the question, "how are you," "good" or "well"? 2. If the question is "how are you doing," what is the correct response? And, of course, the main question is WHY?

The response:

We should note at the outset that conversational or dialectic English is often different than grammatical, formal, or "business" English. So this is an opportunity to point out to the students how the language we use in daily life or in our homes is not necessarily the language we use in the business world.

For example, the language of rock and roll, even written by Liverpudlians, is almost always in informal dialect. You simply couldn't sing, ":You aren't anything but a hound dog," or "Your Mama doesn't dance and your Daddy doesn’t rock and roll." (Although "Whom do you love?" wouldn't hurt.)

Similarly, in daily life, many Americans say, "You're doin' good" as a compliment. If they used the correct, "You're doin' well," among friends, those friends might subconsciously think, "What's got into you?" Similarly, we all say, "It's me," when we pick up a phone, when it should be, "It's I."

That said, correct answers to "How are you? ' and "How ya doin'?" are either "I am well" or "I'm doin' well."

"Well" is an adverb that answers the ques tion "how?" "Good" is an adjective that would have to modify a noun or pronoun. The answer "I am good" is grammatically correct -- and certainly a common, useful response in everyday conversation. But the grammatical meaning is just what it says--- the person is good---a good person, a religious person, maybe. In the answer "I am well," well is an adjective meaning pretty much "in good health." It is an appropriate response to the question "How ya doin?" because it states that you are in good health or good spirits, which is really what the question is asking.

Note: the word "fine" is interchangeable with "well," since it means basically the same thing and -- like "well" -- it is both an adjective and an adverb. (The word "finely" is going out of use in its definition as "in a fine manner, extremely well." You wouldn't say "I am doin' finely." But we still use it in reference to tuning or smallness, and a "finely tuned instrument" or "finely ground coffee.")

Let's compare this exchance to the French, who ask, "Ca va?" Literally, "It goes?" The response is either, "Ca va." or "Ca va bien." It goes, or it goes well (the adverb). (Or "Comme ci, comme ca" - Like this, like that-- the equivalent of our "so-so.")