As an educator who spent most of my life in industry, I agree with the general tone of the OP, in that dry numeracy is, to me, not practical in an education sense, especially with teens, and especially with text books often written so poorly. My HS math was so abysmal that I thought I had no aptitude, but later in college when I did an engineering qual, I came top of the class, and loved calculus. Relevance, interest and fun are often absent in HS numeracy, perhaps because there is so much to cover that there's little time to have some fun with it. This year I'm trying to add science into how I teach numeracy, knowing that at least I can spark a little relevance and fun. Bottle rockets anyone?