N., my experience with my dysgraphic ds has been that the WJ-III Tests of Achievement were *not* good tests to use when advocating for acceleration. They are *great* tests to use when you're trying to determine what challenges a 2e child is having because they use a combination of timed/untimed and oral vs handwritten responses - but for a child who is dysgraphia (or students with other types of disabilities) - you'll see results in some of the subtests that are telling you what the disability/challenge is, not what the student's true level of knowledge is. The tests that have helped us most in advocating for our ds were achievement tests given through the school (whichever achievement tests your school uses - not the state test but widely used tests such as ITBS etc), and it is important that those tests be given with the students with the accommodations they receive for their disability (for my dysgraphic ds, testing accommodations include extended time, and use of a word processor for essay questions).
If your ds hasn't had achievement testing in school yet another thing that was helpful for us in advocating were work samples.
I also want to encourage you to advocate for the level of instruction you feel your ds needs, and if/when the school raises concerns about the writing or whatever, ask the school for help with extra instruction or remediation or accommodations or whatever you think will work best to allow him to participate in the higher level while still working on the basic skills he needs in his areas of challenge. It's really important to give our children *both* experiences, and for some kids (my ds is one of them), it actually *helps* to be given higher-level classwork while working on remediation of a very basic skill such as written expression.
Best wishes,
polarbear
