### Number Sense
Number sense refers to a person's general understanding of numbers and operations along with the ability to use this understanding in flexible ways to make mathematical judgements and to develop useful strategies for solving complex problems (Burton 1993; Reys 1991). It is about developing an understanding of quantity and the ability to use quantitative ideas in everyday contexts.
In the elementary grades, number sense involves counting how many, constructing relationships among numbers of discrete items, composing and decomposing quantity through the operations of addition, subtraction, multiplication and division, and being able to transfer understanding from context to context. Young children enter school already curious about number and size, with ideas about how to join, remove and split quantities (RAND Mathematics Study Panel 2003).
In later years, number sense involves approximating, choosing and translating among various representations (i.e., decimals, fractions and percents); building conceptual, procedural and computational fluency using integers, rational and irrational numbers; and capacity to deal effectively with the quantitative aspects of life (RAND Mathematics Study Panel 2003).
Developing a sense of quantity happens gradually and as a result of exploring, reasoning, investigating and visualizing quantity in a variety of meaningful contexts. Acquiring number sense is a lengthy process (Donovan and Bransford 2005). |