If kids are studying for a test, they're not going to learn anything. We all know that from our own experience.
For one thing, studying language is by itself a part of a study of human intelligence that is, perhaps, the central aspect of human nature. And second, I think, it is a good model for studying other human properties, which ought to be studied by psychologists in the same way.
Descriptive grammar is an attempt to give an account of what the current system is for either a society or an individual, whatever you happen to be studying.
What the polls don't tell you is, though other polls do, is that if you do a study of CEOs, top executives in corporations, they're liberal.
