Without acceleration, I think the public school is impossible, since D reads at 3rd-4th grade level and has taught himself through at least through second grade math in about the last five months. So he won't learn anything in first grade. His behavior is on the young side, though, and we know from talking with them this year that the school administration is very strongly opposed to accelaration.
That's a tough combo, but it could still work. Do you know how your district pans out for GT kids in general? Are there many identified? A good group of peers in a class can be just as good, and sometimes even better than acceleration. We've found a bit of both to be enough to make things doable for us.
FWIW, our district could probably be classified as "strongly opposed to acceleration" as well, but with a lot of persuasion, lots of data and persistence, we've been able to take our school into "never before charted waters", and so far it's been pretty smooth sailing.
Best wishes as you explore your options!