Everyday common sense and school mathematics

In recent years, proposals have been made to build mathematics teaching more closely on children's informal knowledge, i.e. on concepts and strategies formed in natural, everday settings. The article focuses on questions concerning this trend, more specifically on issues concerning how and in what sense children benefit from everyday common sense knowledge when they learn mathematics at school. Three empirical examples, collected within a field-based research project at the intermediate children, when using their everyday life experience, sometimes fail to make mathematical sense of a given task. Two factors which complicate the creation of links between common sense and mathematics are discussed: one that deals with the problem of using everyday life experience as a basis for abstracting mathematical ideas, and one which concerns the pupil's abilities to interpret an assigned task in a mathematically relevant way.