Of course, she should already have read the IEP. But this teacher sounds like the type who won't have done that and doesn't like special pleading.
Usually these battles work best when kept specific. The IEP is your easiest way to do that. A principal will often tend to side with a teacher whose methods aren't all that effective, because it's hard to force the teacher to change old habits and there's an "us vs. them" cohesion about school staff; but they will not usually back up a teacher who's violating the law.
I'd use the IEP. I'd also get that special ed teacher into this conversation right away, as well as the person who administers special ed services in the building. And document everything in ink: dates, missed assignments, conversations. It's likely everybody knows this teacher isn't doing right, and pressure from the rest of the staff may be the best way to help those other kids indirectly.
DeeDee
