Impact of Inquiry-Based Labs on Undergraduate Chemistry Learning Outcomes

Thesis Abstract

The study investigates how inquiry-based laboratory (IBL) approaches influence undergraduate chemistry learning outcomes in introductory and general chemistry courses across three public universities. Persistent concerns about traditional expository laboratories have driven this inquiry to determine whether student-centered, inquiry-driven practices enhance conceptual understanding, procedural fluency, enquiry skills, and scientific attitudes, particularly in diverse student cohorts. The aim is to evaluate the effectiveness of IBL on multiple dimensions of learning and to identify pedagogical conditions that maximize impact. Specific objectives include (1) comparing learning gains in conceptual understanding, assessed by the Chemistry Concept Inventory and course exams, between IBL and traditional labs; (2) examining changes in higher-order thinking and scientific inquiry skills using a validated Performance-Assessment Rubric and think-aloud interviews; (3) assessing shifts in motivation, self-efficacy, and attitudes toward chemistry via the Chemistry Attitudes and Motivation Inventory; and (4) exploring mediating factors such as instructor facilitation quality, collaborative group dynamics, and resource availability. The study adopts a quasi-experimental, mixed-methods design featuring pre-test/post-test measures and a concurrent qualitative strand. Population comprises first- and second-year undergraduate chemistry students enrolled in six sections of General Chemistry I and II during two consecutive academic terms. A total of 360 students will be recruited, with classes randomly assigned to the intervention (n ? 180) implementing IBL protocols and the control (n ? 180) continuing with traditional labs. Data collection instruments include standardized assessments (Chemistry Concept Inventory, concept inventories tailored to laboratory understanding, and course-grade data), a Performance-Assessment Rubric for laboratory skills, Think-Aloud Protocols with a purposive subsample (n ? 24), and validated psychometric scales assessing motivation and attitudes (MOSAIC-chem). Instrument validity and reliability will be established through content validation by chemistry education experts and pilot testing (Cronbach’s alpha targets ?0.70 for internal consistency). The intervention comprises structured, inquiry-driven lab activities designed around contemporary green-chemistry and analytical techniques, with explicit prompts for hypothesis formation, data collection, analysis, interpretation, and reflection, implemented over a 12-week term. Instructors will receive standardized professional development focusing on inquiry facilitation, formative assessment strategies, and equitable group-work practices. Data analysis employs a combination of statistical and thematic methods. Quantitative analyses will include ANCOVA to compare post-test scores between groups while controlling for pre-test performance, multivariate ANOVA to examine interaction effects across subgroups (gender, prior achievement, and major), and hierarchical linear modeling to account for nested data at the class level. Regression analyses will test mediation models to determine the extent to which laboratory engagement and collaboration mediate learning gains. Qualitative data from think-aloud sessions and interview transcripts will undergo thematic analysis using an iterative coding framework to identify patterns in cognitive strategies, problem-solving approaches, and epistemic beliefs. Triangulation will be used to integrate quantitative and qualitative findings, enhancing construct validity and interpretive depth. Key expected findings include significantly higher gains in conceptual understanding and laboratory skills for the IBL cohort, improved performance on higher-order thinking tasks, and more positive shifts in motivation and attitudes toward chemistry. It is anticipated that the magnitude of effects will be moderated by instructor proficiency in guiding inquiry and the effectiveness of group dynamics, with larger gains observed in cohorts receiving intensive professional development and structured reflection opportunities. The study contributes to knowledge by providing robust empirical evidence on the efficacy of IBL in real-world undergraduate chemistry laboratories, clarifying the roles of facilitator quality and collaborative processes as mechanisms of change, and offering a scalable model for implementing inquiry-based practices within standard undergraduate curricula. Based on the findings, the study will formulate actionable recommendations for curriculum designers, department chairs, and instructors, including guidelines for designing IBL activities aligned with course objectives, assessment harmonization, and professional development programs. It will also identify contexts where IBL yields the greatest return on investment and propose strategies to support students with diverse backgrounds to ensure equitable benefits from inquiry-based laboratory learning.