Background: A key question in K-12 STEM education is how best to guide students as they engage in exploratory learning activities so that students develop transferable knowledge. We investigated this question in a study of teacher talk guidance of an exploratory activity called Invention. In this study, teachers worked one-on-one with students, guiding them as they attempted to invent ratio-based equations of physical science phenomena. We applied the interactive, constructive, active, and passive (ICAP) framework as a theoretical lens through which to explore different forms of teacher talk guidance and resulting student talk. The ICAP hypothesis predicts that constructive engagement leads to greater learning than active engagement, which in turn leads to greater learning than passive engagement. However, students do not always enact the type of cognitive engagement that teachers prompt. In this paper, we work towards three goals: (1) to explore the forms of cognitive engagement prompted by teachers and enacted by students in their talk, (2) to test the ICAP hypothesis in the novel context of teacher-student dialog during Invention, and (3) to identify effective forms of teacher talk guidance for Invention activities and other exploratory STEM learning tasks. Results: While the majority of student talk was active, teachers produced an even distribution of constructive, active, and passive prompts. Teacher and student talk types tended to align, such that students often responded with the type of cognitive engagement teachers invited, with the exception of passive talk. In general, teacher talk showed the most robust relationship with students' abilities to transfer, while teacher-student dialog demonstrated a weaker relationship with transfer, and student talk was not significantly related to transfer. Some evidence for the ICAP hypothesis was found, most prominently in teacher talk, where constructive prompts positively predicted transfer, active prompts were not related to transfer, and passive prompts negatively predicted transfer.
Conclusions:This research implies that teachers should use a large proportion of constructive prompts and relatively few passive ones when guiding students through Invention tasks, when the goal is to provoke transfer of learning to novel contexts. This work also extends the CAP portion of the ICAP hypothesis to teacher-student dialog and underscores the teacher's critical role in encouraging students to cognitively engage with exploratory STEM tasks in effective ways.