blackcat, our ds uses the Rory Story Cubes also - we first used them to help him practice writing fiction, and he now uses them when he's got a writing assignment and he's stuck - even though he doesn't necessarily use what he gets from the cubes in his assignment, the act of rolling the cubes and trying to come up with something to put together a brief "story" helps somehow get his brain working on the "real" assignment.
As far as the teacher at school, she's an issue - but the larger issue is understanding what's behind your dd's struggles. I think you're going to have to do more digging on your own and follow-up with a request for a comprehensive eval at school. I'd put the paperwork in now for that request - you have enough evidence that it's warranted (difficulty with written expression). I wouldn't quote the private test scores on the written request for the school eval, I'd just state the issues you've observed at home re generating written expression (can include handwriting, getting thoughts out, organization of writing), and any examples your dd can give you from school. If there are only 6 weeks of school left, that's 30 business days, which I'm guessing is less than the time limit required to complete an evaluation in, and it's a busy time of year at school for folks who are involved in IEP eligibility evaluations because it's the time of year when IEPs for the next school year are put together and finalized for the students who already have IEPs - in other words, I'm guessing there won't be an actual eligibility eval until the beginning of the next school year, although there should be a meeting to determine if the school will go through with an eval. So you'll have the summer to continue to pursue what you can privately at home re understanding what you can re what's going on.
Anyway, that's jmo - I think the focus needs to not be on the teacher, but on trying to figure out what's really behind your dd's issues with writing. That's not saying it's not important to continue to advocate as much as you can with this teacher, but instead to not lose focus on the larger issue while getting through the day-to-day at school.
Hang in there!
polarbear
