“3. (+) Use special triangles to determine geometrically the values of sine, cosine, tangent for π/3, π/4 and π/6, and use the unit circle to express the values of sine, cosine, and tangent for π–x, π+x, and 2π–x in terms of their values for x, where x is any real number.”
Was tau taken into consideration while forming the standards? It really is a completely superior notation to the use of π and if anybody was really going to be able to put some muscle behind the introduction of tau notation, it would be CCSS.
Unfortunately the $\pi$ conspiracy extends beyond the shores of this country. One of the specifications for the writing of CCSS is that they be internationally benchmarked, and so we were unable to adopt this admittedly enlightened suggestion from Bob Palais. Alas, this change will have to come from the grass roots, perhaps with the formation of a $\tau$-Party who paint themselves in patriotic colors on $\pi$-day and stage protests across the country against the tyrants who make them write so many 2s.