Thank You Bill Bennett

This morning, on Bill Bennett's Morning in America, Bill used the phrase "fewer calories." This caught my attention because most voices I hear use "less" whether that is correct or "fewer" should be used. How can you tell the difference? If what you are referring to can be counted, you have fewer; if not, less. Some examples: less gasoline, fewer gallons; less milk, fewer quarts; less worry, fewer worries. Have you got it now?
My greatgrandparents came here from Germany and, since they had to learn English, insisted that their children learn to speak and write English correctly. My grandfather was a real stickler; my mother was a newspaper proofreader, editor and reporter; and I was taught so well at home that, when we had grammar and usage exercises in school, if it sounded right to me, it was. I often find myself wincing or shaking my head at the way American English is so regularly mangled today.
Henry Higgins had it right in "My Fair Lady." In the song "Why can't the English teach their children how to speak" there is a line that says, "In some places English completely disappears--why in America they haven't used it in years!" And how are children supposed to learn what is correct if the people they hear in the media as well as their friends and family speak incorrectly, and political correctness prevents their teachers from telling them what's right or wrong?