Hi Keet.
I'm an OT and also a parent of a GT kid. Has your son had his vision checked? Did the OT test fine motor skills specifically? Are there other motor coordination issues? Is the psychologist at the school testing for dysgraphia?
Typically, scores on standardized tests that are in the 15th% or lower will get someone's attention and be considered a delay. As for waiting or taking action privately, I would base that decision on whether or not your son is succeeding, relatively speaking, at school. If the handwriting is causing undo stress and he is frustrated, failing or struggling then you maybe should do whatever you can afford to do right now. But if he is getting by and you feel the school isn't going to drag it out too much longer, then waiting is fine. Just remember that he won't get any services from the school over the summer.
Is there anyone at the school you can call on as an ally? Perhaps the OT could advocate for the staff to get their testing completed sooner rather than later.
