I'll join the chorus of how cool that is.
The things I'd ask for: extensive documentation, to make sure no one can think of a good reason to stick your kid into grade level math in a later year. (They may think of bad reasons, but don't make it too easy.)
Absolutely no grade level homework. He doesn't need it, and the point is for him to get out of it.
In fact as others have said, as little homework as possible. Maybe fluency I timetables stuff, but not one worksheet a day homework. He's got an hour one on one, he is surely way advanced, no need to pod any more work in the after noons unless it's stuff he seeks out on his own. That said, you may want the time in. The afternoon for extension work or enrichment in language arts, which he may need as well, but which Is easier to provide as differentiation Ina regular classroom.
I'd make sure the tutor works on weaknesses,but doesn't over look strengths, ie presenting your work legibly and neatly, organization etc, but work on this with math at his level.
Enjoy it while it lasts! From a policy point of view, this is really not a sustainable service, expensive, envy-inducing and without any (with a DYS level child, probably questionable and ultimately unsuccessful attempt to provide a cluster of peers, but no need for you to look the horse in the mouth as it were.
