The research is pretty clear on the limited value of homework for kids in elementary school. Even in HS, I believe only math HW has been shown to have learning benefits. Of course, if they aren't learning anything IN school, then that's frustrating, but sort of different. I agree that the HW policy shouldn't disallow you from getting the spelling words early to accommodate for your DS's needs, of course!
My DD8 has an average of an hour and a half of HW a night, often two hours, and it's nearly killing us. She is somewhat slow, but not excessively so. Even if you did everything at a very brisk pace, there's no way it would take less than an hour. I suspect part of the reason she gets so much is that she is at a gifted magnet and some of the parents are pretty Tiger Mom-ish (and then many are not at all--interesting mix).
