What do under-prepared students learn about measurement from introductory laboratory work?

This study investigates changes in students' understanding of various aspects of measurement before and after participating in two different introductory laboratory courses at two universities in South Africa. Students' ideas were sought using a probe into their understanding of data collection, data processing and data comparison. The responses were analysed using a model which identified subjects as adhering to either a point or set paradigm. Considerable gains were made during instruction with both groups, though some important differences were identified between them. Neither group could be identified after instruction as full adherents to the set paradigm which was a goal of the instruction. Rather, the majority were found to use ad hoc or rote set action, while using point reasoning.