I actually discarded DS's math homework that was completely inappropriate, and substituted something that was an appropriate challenge. This works for younger kids where grades don't really matter (if they are graded at all), but it's harder to pick and choose what your kids are going to do in older grades. I did this with two different teachers and I think one hated me because of it, and the other couldn't care less. I think she was of the mindset that second graders shouldn't even be getting homework, but she has to do what the district directs her to do. So she didn't care that he never did the homework.
Since then we moved DS to a school where they simply move the kids to where they need to be. So for DS, that meant going from second grade to fifth grade for math. The math schedules in the school are more or less aligned. It's not rocket science, but most schools wouldn't even consider doing anything like that. For reading, there are 3 teachers and each teacher takes a different group depending on ability level. That's how it is for math, too, but DS was so far out of range, they just moved him to a different grade which has it's own math ability grouping and the 3 teachers split up the kids according to ability level. So he is in a group that is doing pre-algebra.
Since the school has him doing the right level I don't need to "houthouse" or after-school anymore, and it's been a relief to no longer have to worry about him making no progress or acting like a lazy slug.
I think that many/most schools could follow a similar model, but they are too stuck in a traditional mindset and unwilling to consider/organize other possiblities.
