Some of the CC math I've heard discussed is monkey motion intended to teach by an attempt to systematize "tricks of the trade" which I believe are best learned after a student has solid experience with proven, straightforward methods of obtaining correct answers.
Can't argue with that.
The problem I saw with their series on approximating and estimating, like your 3x3=9 example, is that the numbers given were so blatantly simple - even from my daughter's view, that she kept assuming there should be more to it, and over thought the process.
Those things should become 2nd nature with experience. You can't instruct common sense.
