I'll also add, back to the topic of the original thread...
we've seen this in those spiffy self-congratulatory pre- and post-curriculum tests of student learning...
I'm a packrat and a documentarian. True story, that. When you have a 2E kiddo, you learn through the school of hard knocks that you want it in writing, and YOU WANT YOUR OWN COPY.
Anyway.
My DD was forced to take these RIDICULOUS 'tests' twice a year from 3rd through 8th grade. Well, subtracting the year that she skipped.
Her scores frequently reflected a
loss in learning.

I have the scores, so I know. Scores that go from 99% or 100% to 93% or 94% are showing 'decreases' in performance, are they not?
So the upshot here is that we had proof that what they were doing with her each year was NOT BENEFICIAL TO HER educationally.
(Well, okay, the truth is slightly more complicated. What
is true is that she already knew the grade level curriculum, in spite of the acceleration, and that her scores were generally somewhat lower at the end of each year because of end-of-year stresses.)
The reason that I mention this is that I noticed something....hmmm...
funny... one day, as I was looking at her educational records.
Recall, these are not placement tests. Hypothetically, these are to let the school know how they are doing, let students know how much they've learned, rah-rah-rah.
Someone had oh-so-helpfully "CORRECTED" this obvious error and flipped her actual scores so that they showed the improvement that they were supposed to show.Moral of the story is this: never rely on what you're told. get copies. Keep copies. Keep your eyes open. We have kids that tend to upset administrator agendas.
I frankly didn't care enough to burn the human capital fixing this particular problem in light of the other cooperation that we need from DD's school. But if it had mattered somehow, I'd have been equipped to fight for the truth.