If he was privately assessed, what advice or recommendations did you receive with the report? Before you share the scores, my advice would be to do what you are doing here (getting more context) but also go read up on the publicly available articles on the Davidson site about advocacy and educational options for highly gifted children. Those were very helpful in educating ourselves and some were good to share in the conversation with school personnel. The first guidebook on this page is a great start. http://www.davidsongifted.org/youngscholars/Article/Davidson_Young_Scholars___Guidebooks_375.aspx

I may be wrong, but I think that GAI might be a DYS qualifying score.