Public discourse concerning STEM has an increasing influence on mathematics education, yet the exact role that mathematics plays in STEM is hard to define. I compare STEM to numeracy to investigate how mathematics is repositioned in these two discourses. Each is analysed in terms of rhetorics that argue for the worth of mathematics education. While numeracy viewed mathematics as worthy for critical citizenship, STEM argues that mathematics has worth due to its support of the innovation required for productivity growth. Analysis of the rhetorics is argued to support the mathematics education research community response to changes in public and policy discourses regarding mathematics.