Number bonds? Umm, okay. Decomposing numbers in kindergarten. Umm.
I did a lot of reading about the ideas behind Common Core math (stuff written by the people who wrote the standards), and my understanding about CC addition is that the whole point is that addition means
combining things. IMO, "number bonds" don't really...do that. I suspect that they just create confusion and encourage kids to memorize an algorithm.
A huge part of the problem with the CC is that the standard authors just kind of figured that the textbook people would make Wonderful Books and that the teachers would rush out to learn about CC methods. Predictably, neither of these things has happened, and one of the 3 primary people who wrote the math standards has to tutor his daughter in math.
I am not making this up. At the same time, you might want to see if your daughter's confusion about the block problem was trivial or if she really didn't understand that she was being given a subtraction problem. She may understand what subtraction is algorithmically, yet still might not always recognize when she needs to use it. This is common, I think. A principal I know used to talk about typical curricula teaching kids to do an algorithm, but not how to recognize when it was needed.
Give her a similar problem. If she doesn't get it, you might want to do a few exercises with her, and maybe dream up a few more that ask her to apply an algorithm. Personally, when I'm teaching a lesson like this to my kids, I don't give them the answer. I try to get them to think their way through the problem, as moments like this are the ones that honestly challenge a gifted kid who can do straightforward worksheets in her sleep.
If she does get it or eventually figures it out, ask her how she got to the answer. This, IMO, is precisely when a student should be explaining an answer (as opposed to CC worksheets that want kids to explain every little algorithm).
