I remember my own frustration with elementary school math, echoed in the standards I read for DD a few years ago. They spent a full month every year on place value - increasing it one place per year: ones and tens in K, to 100 in 1st, hundreds in 2nd, thousands in 3rd... At a school math night I tried to express to a teacher that this was the SAME PROBLEM. It is not harder to add 10,000 + 30,000 than to add 1 + 3, once you understand place value; and if you don't get place value, then 100 + 300 is already too hard. The math teacher looked entirely baffled. I take from this that for many kids, I'm wrong and they actually do need to spend time learning that each new place also works on a tens system.
2nd grade math seems to be the prealgebra of basic numeracy: making sure all the holes are filled so that once math facts are learned, kids will be able to put them to use. There is not a lot of new content, but a lot of review and closer-to-mastery expectations.
