I'm going to copy the quote I cited in another thread recently, which indicates the standard federal special education law says schools should use. (OCR is Office of Civil Rights. You do not want to mess with them, if you are a school.):
From this:
http://www2.ed.gov/about/offices/list/ocr/letters/colleague-201607-504-adhd.pdf(emphasis mine):
"Someone with ADHD may achieve a high level of academic success but may nevertheless be substantially limited in a major life activity due to his or her impairment because of the additional time or effort he or she must spend to read, write, or learn compared to others.44 In OCR’s investigative experience, school districts sometimes rely on a student’s average, or better-than- average, grade point average (GPA) and make inappropriate decisions."
Substitute dysgraphia (or, more properly, in the school context, Specific Learning Disability in written expression) for ADHD.
