National Council of Teachers of Mathematics
The National Council of Teachers of Mathematics (NCTM) was founded in 1920. It has grown to be the world's largest organization concerned with mathematics education, having more than 80,000 members across the USA and Canada, and internationally.
The National Council of Teachers of Mathematics presents itself as "the public voice of mathematics education, supporting teachers to ensure equitable mathematics learning of the highest quality for all students through vision, leadership, professional development, and research."