Functions and Strategies of Teachers' Discursive Scaffolding in English-medium Content-based Instruction

Although decades of research have documented scaffolding in second language learning, providing scaffolding in content-based instruction (CBI) has remained under-explored. This qualitative study investigated teachers' discursive scaffolding strategies and functions and L2 students' reciprocity to teachers' scaffolding in science CBI. Four teachers and 30 bilingual students were selected through convenience sampling from an international school. The audiotaped recordings of 24 hours of classroom instruction were transcribed and analyzed based on discursive scaffolding strategies (Walqui, 2006) and scaffolding functions (Wood, Bruner, & Ross, 1976). The deductive content analysis of data demonstrated that the most frequent scaffolding strategies were bridging and schema building while contextualizing and developing metacognition were barely observed. Furthermore, the findings revealed that scaffolding functions were mostly aimed at providing the idealized version, recruiting pursuit of a goal, and controlling frustration, whereas marking critical discrepancy was rarely employed. It can be concluded that scaffolding strategies and functions mostly pertain to enhancing students' comprehension rather than developing metacognition. These findings have implications for the applicability of types of scaffolding strategies and functions in CBI classrooms.