Reflection of a lesson can be done with Lesson Study (LS). The application of lesson study using Transcript-Based Lesson Analysis (TBLA) is unfathomable in Aceh. Therefore, adding a new framework to analyze learning practice with evidence-based analysis is essential for teaching quality improvement. This research aims to analyze the learning process of building concepts, attitudes, student engagement, teacher pedagogical decisions, and learning activity dominance using a TBLA-Based Lesson Study. The Research method is a mixed method with typology concurrent triangulation identical sampling, signifying that quantitative and qualitative data are obtained simultaneously. The learning process was carried out in class XI MIPA 1 SMAN Modal Bangsa Aceh using the Modeling Instructions learning model with Neuron PHET Simulation media. Data is collected using audio and video recordings and observation worksheets, in which the recordings are transcripted into conversational dialogue later on. The quantitative analysis calculates the number of keyword frequency forming concepts, language functions, sentence length, and the number of words to comprehend class activity dominance. Meanwhile, the qualitative analysis focuses on gestures, student engagement, and teachers’ pedagogical decisions. As a result, there is a process of ideas growth and right concept formation, dominant pointed gestures, high engagement, and activities dominance by students (Students Center). Potential pedagogical decisions of teachers are the selection of heterogeneous group members, time effectiveness strategies, and the application of probing ask techniques. Learning analysis using TBLA guides teachers to perceive their teaching quality as a reflection of the development of further learning.
Keywords: Lesson Study, TBLA, Reflection, Audio, Video