The Effects of Inquiry-Based Learning on Critical Thinking Skills in Argumentative Essay Writing: A Study of Advanced Level English Language Learners
Mohammed Hussain Fathima Husna
ABSTRACT
Writing argumentative essays is one of the most demanding tasks facing second-language learners, requiring not only linguistic competence but also the capacity to reason, weigh evidence, and organise ideas persuasively. This study examines the impact of Inquiry-Based Learning (IBL) on the critical thinking skills that underlie argumentative essay writing among Advanced Level English Language learners in Sri Lanka. Using a pre-experimental, time-series design, thirty students selected through comprehensive sampling completed three argumentative essay writing pre-tests, received a four-week IBL intervention, and then completed three parallel post-tests. Quantitative data were analysed descriptively in Microsoft Excel, while qualitative data from focus group discussions and student reflective journals were analysed narratively. Mean essay scores rose from the high 30s in the pre-tests to the mid-60s in the post-tests, and error analysis using rubric showed marked reductions across content, organisation, vocabulary, language use, and mechanics, with mechanics-related errors, particularly capitalisation, remaining the most persistent difficulty. Qualitative findings indicated that students developed stronger interpretation, analysis, evaluation, inference, explanation, and self-regulation skills [1]. The findings support IBL as an effective pedagogical approach for developing critical thinking in second-language writing instruction and carry implications for curriculum design, teacher training, and further research into inquiry-driven language pedagogy.
