So you might have heard about the fuss, in the NYTimes, over Junie B. Jones, who doesn't use "proper" English.
The spunky kindergartener (first grader in more recent volumes) is prone to troublemaking, often calls people names and isn’t averse to talking back to her teachers. And though she is the narrator of the stories, she struggles with grammar. Her adverbs lack the suffix “ly”; subject and object pronouns give her problems, as do possessives; she usually isn’t able to conjugate irregular past tense verbs; and words like funnest and beautifuller are the mainstays of her vocabulary.
My kid loves Junie B. , not to mention Hank the Cowdog (he's from Texas and says ain't and fixin to). Amazingly, she loves these books because Junie B. and Hank get the grammar wrong: because she knows more than they do. (Hmm. Wonder why the parents in the NYT article can't imagine that possibility?) She likes snickering over the characters' mistakes.
She also likes the other mistakes Junie, and Hank, makes -- these are trickester tales for 8 and 9 year olds. Junie plagiarizes, in Junie B Cheater Pants. The appalling outcome, for my kid, went a lot further than all of my rants about the evils of plagiarism (and yes, there have indeed been many) could ever have gone. Hank thinks his barking makes the sun come up. Will I ever have to explain the post hoc ergo facto hoc fallacy to my kid now? Nope.
Nor do I have to tell her that "I'm fixing to take me a bath" is not standard English.
Because she ain't no idiot, that's why.
For more on this, read here.