Learning Multi‐unit Number Concepts and Understanding Decimal Place Value

Abstract

Research indicates that many errors in secondary school mathematics can be attributed to lack of understanding of decimal place value. Recently it has been suggested that this arises from an underlying weakness in integer place value concepts and perception of multidigit numbers in unitary terms rather than base ten, multi‐unit structures. Development of place value and multidigit number concepts was examined in individual interviews with 262 primary school pupils, aged between 7 and 12 years, using subjects’ concrete representations of written numerals and associated verbal explanations. Almost all the children had some understanding of integer place value; most older children had multi‐unit concepts of three‐ or four‐digit numbers; but two‐digit numbers, especially values of 20 or less, were frequently perceived in terms of units by all age groups. This was particularly common for the value ten where 55% of subjects displayed unitary concepts. Implications for understanding and teaching decimal place va...