The development of primary students' knowledge of the structured number line

Abstract

This paper investigates how primary students’ knowledge of the structured number line develops over time. Effective number line use is impacted by an understanding of this graphic as a representation that encodes information by the placement of marks on an axis and an appreciation that these marks are representations of length rather than labelled points. Generally, the results revealed development of number line knowledge over time. However, although correlations between number line items were positive, they were only moderate or low. Additionally, there was low shared variance between items even though students solved the same items in three consecutive years. Noteworthy were the statistically significant gender differences in favour of boys over the 3- year-period − findings that warrants further investigation.