On Jul 15, 2013, at 9:55 AM, kirby urner <email@example.com> wrote:
> I'm saying that the tetrahedron may also be used as a model of 3rd powering i.e. you have a dial you rotate clockwise / counter-clockwise to boost-diminish the edge sizes of a tetrahedron from between 1 and 3. The thing grows and shrinks from volume 1 to 27 and every value in between, and its volume is precisely a 3rd power of the edge length. Why? Because we *define* a unit edge tetrahedron to have volume 1. Can we do that? Yes. > > Is there a reason to *never* show this in the classroom? I'm saying the Common Core gives us an opportunity to brand curricula as not just "aligned" but extending "well beyond".
I suspect the reason is that it is contrived and doesn't make and sense.
 contrived: deliberately created rather than arising naturally or spontaneously.