Some of that is just bad material (#3, shapes that should be shaded are not shaded). Others try to explain how at least I do arithmetic mentally (the particular

Some of that is just bad material (#3, shapes that should be shaded are not shaded). Others try to explain how at least I do arithmetic mentally (the particular example 7 + 7 feels silly because the answer was drilled to my brain in primary school, but the idea of decomposing number to parts that easier to sum together is sound -- and it feels like nice intuition to algebraic way of thinking). On the other hand, insisting in drawing graphical representations might be boring and feel silly if you already got it. In other words, the Common Core seems to get flak because some of the material is simply bad and sometimes seems not to have good idea how to convey the Common Core ideas.