Development of turn and turn measurement concepts in a computer-based instructional unit

This study investigated the development of turn and turn measurement concepts within a computer-based instructional unit. We collected data within two contexts, a pilot test of this unit with four third graders and a field test in two third grade classrooms. We conducted paper-and-pencil assessments, interviews, and interpretive case studies. Turns were less salient for children than 'forward' and 'back' motions. Students evinced a progressive construction of imagery and concepts related to turns. They gained experience with physical rotations, especially rotations of their own bodies. In parallel, they gained limited knowledge of assigning numbers to certain turns, initially by establishing benchmarks. A synthesis of these two domains - turn-as-body-motion and turn-as-number - constituted a critical juncture in learning about turns for some students. Some common misconceptions, such as conceptualizing angle measure as a linear distance between two rays, were not in evidence. This supports the efficacy and usefulness of instructional activities such as those employed.