We are having a similar problem, also with 1st grade. DS is complaining that he's bored and the work is too easy. When I conferenced with the teacher she showed me all the differentiation (and it is pretty impressive) that she is doing in Language Arts. She admitted they are focused on reading right now, because a lot of the kids aren't even reading yet. This is a magnet GT program and DS is reading at a third grade level.
Basically, they are doing nothing in math beyond review so far, because they are focused on getting all the kids reading a little better. I mentioned this to the principal and she said, oh well, you know they have to review. Meanwhile, sheets and sheets of +0, +1 and +2 problems. Ugh. I think they started -0 last week.
I'm grateful that they are at least differentiating in Reading, but am asking DS to be patient with Math, at least for now.
Maybe your child's school has a similar approach?