Differential Participation During Science Conversations: The Interaction of Focal Artifacts,Social Configurations,and Physical Arrangements

Recent conceptualizations of knowing and learning focus on the degree of participation in the practices of communities. Discursive practices are the most important and characteristic practices in many communities. This study was designed to investigate how the content and form of classroom discourse was influenced by different combinations of artifacts (e.g., overhead transparencies, physical models), social configurations, and physical arrangements. Over a 4-month period, we collected data (video-taped activities, interviews, ethnographic observations, artifacts, and photographs) in a Grade 6-7 science class studying a unit on simple machines. Four different activity structures differed in terms of the social configuration (whole class, small group) and the origin of the central, activity-organizing artifact (teacher designed, student designed). This study describes how different artifacts, social configurations, and physical arrangements led to different interactional spaces, participant roles, and levels of participation in classroom conversations and, concomitantly, to different discursive forms and content. The artifacts had important functions in maintaining and sequencing conversations. Depending on the situation and the role of participants, artifacts served as resources for students' sense making. Each of the different activity structures supported different dimensions of participating in conversations and, for this reason, we conclude that science educators teaching large classes should employ a mixture of these activity structures. Overall, students developed considerable competencies in discursive and materials practices related to simple machines.     

Assessing students’ understanding about levers: better test instruments are not enough

This study was designed to investigate variations in students’ responses to lever problems across multiple assessment contexts and formats. Prior to and at the end of a four‐month science unit on simple machines, grade 6/7 students prepared semantic maps, wrote responses to application questions, discussed their written answers, and modelled solutions to practical problems using physical materials. We present data from pre‐ and post‐instruction interviews to show that students’ responses varied in kind and extent across assessment contexts and formats. Such variations in performance are consistent with situated cognition theories which assert that competence is heterogeneous across situations and is a function of interactions between individuals and the contexts in which they perform. Based on these findings, implications are drawn regarding more productive means of assessing students’ understanding in classrooms.