The Influence of Number‐sense on Children's Ability to Estimate Measures

This study aimed at clarifying the relative developmental influences of age, number‐sense and context on primary school children's ability to estimate measures. Children (6‐11 years) were first assessed on three aspects of number‐sense (mental computation, understanding of relative number magnitude and understanding of relations between numbers) and were then assessed on their estimation of length and area within each of two task contexts (a ‘story’ frame and a ‘textbook’ frame). While number‐sense was found to improve with age, estimation did not. However, an ability to use and perceive number relations, together with an understanding of the relative magnitudes of larger numbers, were found to influence children's ability to estimate area. Children of all ages were also found to estimate more accurately in the ‘textbook’ context than in the ‘story’ context. These findings are discussed with reference to the notion of estimation as a situated activity