Two fundamentally important issues discussed in Everybody Counts (National Research Council, 1989) and the NCTM Professional Standards for Teaching Mathematics (1991) are:
These two issues, in particular, have important implications for which mathematics should be taught. At each grade level, the Standards emphasize problem solving, communicating mathematics in a range of modes, mathematical reasoning, and mathematical connections. These four overarching Standards represent the processes and assumptions from which content-specific standards for grade level clusters K-4, 5-8, and 9-12 were developed. The NCTM provides a summary of content at each grade level cluster in a format that realistically looks at what deserves increased attention and what we might give decreased attention in our efforts to improve mathematics teaching and learning.