In mathematics education, number sense can refer to ‘an intuitive understanding of numbers, their magnitude, relationships, and how they are affected by operations.’ Some definitions emphasize an ability to work outside of the traditionally taught algorithms, e.g., ‘a well organized conceptual framework of number information that enables a person to understand numbers and number relationships and to solve mathematical problems that are not bound by traditional algorithms.’
There are also some differences in how number sense is defined in the field of mathematical cognition. For example, Gersten and Chard say number sense ‘refers to a child’s fluidity and flexibility with numbers, the sense of what numbers mean and an ability to perform mental mathematics and to look at the world and make comparisons.’ Researchers consider number sense to be of prime importance for children in early elementary education, and the National Council of Teachers of Mathematics has made number sense a focus area of pre-K through 2nd grade mathematics education. An active area of research is to create and test teaching strategies to develop children’s number sense.
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