Well having made that argument and failed miserably, I'd leave out the standard deviations. When I asked DS's teacher (keep in mind he's supposed to be at a gifted school!) how she handles differentiation in the class, her response was "there is no need, they are all learning at the same pace." I should have shut up but I proceeded and said "Well that's interesting because the kids are so different. It must be difficult to teach them all the same. How do you teach the ones that are really behind the rest?"
Her answer... I kid you not...
"They all need help with coloring. It's a skill that is not natural to most Kindergartners so we really have to work on it. But even the slow ones, LIKE YOUR SON, learn to color by the end of the year."
You've gotten some great advice and I think your meeting will go very well if you can keep it focused on your child and breathe. And breathe some more. I find it very helpful to have a small mint so that as I'm biting my tongue, I don't bite it too hard!
