Those are amazing scores! It appears he is not only exceptionally strong mathematically, but verbally as well. And he has an amazing working memory score with both sections ceiling out at 19. You should look into Epsilon Camp for him. It will be my DD's 3rd year and she looks forward to it all year.
I'm curious as to why the GAI is lower - I'm sure Aeh will chime in!
You should apply to PG Retreat; I don't think they have the same residency requirements as DYS.
https://pgretreat.org/http://epsiloncamp.org/
