Comparative Analysis of Inquiry-Based versus Lecture-Based Methods in High School Biology Learning

Thesis Abstract

The effectiveness of instructional methods in fostering understanding and engagement in high school biology remains a critical concern for educators and policymakers, particularly in the context of evolving pedagogical paradigms. This study investigates the comparative impact of inquiry-based learning (IBL) and traditional lecture-based instruction on students’ academic performance, conceptual understanding, and motivation in high school biology classes. The research aims to contribute empirical evidence to inform pedagogical practices and curriculum development by systematically examining how these instructional approaches influence students’ learning outcomes. The specific objectives are to (1) assess the differential effects of inquiry-based and lecture-based methods on students’ academic achievement in biology; (2) explore students’ conceptual understanding of core biological concepts under each teaching approach; (3) evaluate students’ motivation and engagement levels associated with both instructional strategies; and (4) identify relevant factors mediating the relationship between teaching method and learning outcomes. To achieve these objectives, the study adopts a quasi-experimental research design involving pre-test and post-test assessments complemented by qualitative data collection. The population comprises 600 senior secondary school biology students from six schools in an urban district. A stratified random sampling technique was employed to select two schools per intervention group—three schools employing inquiry-based methods and three employing lecture-based instruction—ensuring representativeness across socioeconomic and academic performance variations. The sample size distribution entailed approximately 100 students per school, totaling 200 students per group (400 participants in total). Data were collected through standardized achievement tests, conceptual understanding questionnaires based on Bloom’s taxonomy, and motivation scales incorporating the Achievement Motivation Scale (AMS). Additionally, classroom observations and semi-structured interviews with teachers provided contextual insights into instructional practices. Quantitative data were analyzed using descriptive statistics, multivariate analysis of variance (MANOVA) to compare group performance on achievement and motivation scores, and multiple regression analysis to identify predictors of learning outcomes. Qualitative data from observations and interviews underwent thematic analysis following Braun and Clarke’s framework to elucidate pedagogical dynamics and student perceptions. Validity and reliability of instruments were established through pilot testing, Cronbach’s alpha coefficients, and expert reviews. The anticipated findings predict that students exposed to inquiry-based learning will outperform their peers on achievement tests and demonstrate deeper conceptual understanding compared to those in lecture-based settings. Furthermore, inquiry-based instruction is expected to lead to higher motivation and engagement levels, mediated by active learning opportunities and learner autonomy. The study hypothesizes that factors such as teacher facilitation style, classroom environment, and student prior knowledge significantly influence these outcomes. This research will augment existing literature by providing rigorous comparative data on the pedagogical efficacy of inquiry versus traditional lecture methods within a Nigerian high school context, addressing identified gaps related to holistic learning outcomes. It aims to extend the application of constructivist theories—particularly Piaget’s cognitive development theory and Vygotsky’s social constructivism—by elucidating how learner-centered approaches facilitate meaningful biological understanding. In conclusion, the study expects to demonstrate that inquiry-based methods offer substantial advantages over lecture-based teaching in promoting academic achievement, conceptual clarity, and learner motivation. Recommendations will include integrating inquiry strategies into biology curricula, enhancing teacher training in student-centered pedagogies, and fostering an educational environment conducive to active scientific inquiry. The findings aim to inform policymakers and curriculum developers towards adopting evidence-based instructional practices that align with contemporary theories of learning and pedagogical effectiveness.