The NCTM publication Principles and Standards for School Mathematics (widely known as PSSM) sets out the essential elements of a preK-12 education in mathematics for present times and future expectations. These Standards were developed by the National Council of Teachers of Mathematics in consultation with teachers, others in education, the leading societies of US mathematicians, and the wider community. They were refined over a fifteen-year period from the initial drafting in 1985, through a first published edition in 1989, to the current Standards 2000. They have been widely, though not universally, accepted across the US, and used as the basis for many state standards, and for the developments of curriculum and assessment materials that were funded by the National Science Foundation.
The main features of PSSM include:

• statements of Principle for each of: Equity, Curriculum, Teaching, Learning, Assessment, Technology
• recognition of everyone's need for a broader range of mathematics than in traditional US curricula, covering
• 5 process categories (Reasoning, Representation, Problem solving, Connections, and Communication), as well as the more familiar
• 5 content areas (Number, Measurement, Algebra, Geometry, Data and statistics)
• mathematics for all students throughout K-12, linking specifations for each of four Grade ranges.

As well as PSSM itself, NCTM offers a wide range of ancillary materials.