Students' talk about rotational motion within and across contexts, and implications for future learning

The investigations reported in this article are part of a larger study conc erned with understanding learning as it emerges from the enacted curriculum which in itself is mediated by: students' views of the nature of science, beliefs about learning, views of laboratory learning environments; teacher' s beliefs about knowing and learning science and knowledge of student ideas about content. In this article, the results of two studies of students' di scourse about rotation phenomena are presented with a particular focus on t he consistency of this talk across different phenomena. Study 1 presents an inventory of students' observational and theoretical descriptions after th ey had been taught rotational motion during the previous school year; it si multaneously constitutes an inventory of students' knowing before another p hysics unit that presupposed knowledge of the first instructional cycle. St udy 2 reports on the same students' discourse after a four-week unit on the dynamics of rotational motion. The results of Study 1 indicate that in spi te of prior instruction, students' observational and theoretical descriptio ns of rotational phenomena were different from scientific canon and inconsi stent within and across contexts. Study 2 further underscores the variation s in student discourse about rotational motion within and across context an d the differences with canonical discourse. More importantly, it illustrate s that only a minority of students provided adequate observational and theo retical descriptions about the dynamics of rotational motion.