This study examined whether the Context-Adaptive Learning Model (CALM) integrated with Task-Based Language Teaching (TBLT) could enhance the English speaking skills and learning engagement of Thai lower-secondary students. CALM is a five-competency framework — diagnostic competency, didactic competency, classroom management, subject matter knowledge, and contextual awareness with reflective practice — that guides teachers in adapting instruction to the linguistic and socio-cultural context of their learners. A classroom action research design of three plan–act–observe–reflect cycles was implemented with 20 Grade 7 students at a municipal school in Khon Kaen Province, Thailand, during the first semester of the 2025 academic year. Six CALM–TBLT lesson plans built around identifying objects, describing people, and describing possessions were delivered across the three cycles. Data were collected through a speaking pre-test and post-test scored with a six-criterion analytic rubric, an end-of-cycle speaking assessment, a 12-item learning engagement questionnaire, and open-ended reflective responses. Descriptive statistics, a paired-samples t-test, a repeated-measures ANOVA and content analysis were used. Speaking scores rose from M = 11.65 (SD = 2.16) to M = 21.75 (SD = 1.48) out of 24, t(19) = 26.84, p < .001, with an extremely large effect size (Cohen’s d = 6.01). No student reached the 70 per cent criterion before the intervention; all 20 did afterwards, and cycle means increased steadily. Learning engagement was very high (M = 4.69 out of 5, SD = 0.33, α = .85). Reflective responses showed a shift from shyness and fear of error towards willingness to speak.
Keywords: Context-Adaptive Learning Model; Task-Based Language Teaching; English speaking skills; learning engagement; lower-secondary EFL learners