My FC told me that in general (and this IS a generalization! Some private schools are fab, of course!) it is easier to advocate with public schools than private because public schools are required to work for all kids. Private ones are a business, and they are well within their rights to say "This is the product we sell: take it or leave it."
In a bad economy, with a school that isn't full, you might have better luck negotiating with a reluctant private school. But if they have a wait list, there's no real impetus for them to serve your child's needs.
I have to admit, from what you're saying, onthegomom, I'm afraid I'm hearing the principal saying, "We're not going to serve your child's needs. Now leave me alone."
(That doesn't mean that you *should* leave her alone. Only that that's what she's saying.)
