Assessing the Impact of Inquiry-Based Learning on Critical Thinking Skills in High School Biology: A Mixed-Methods Study

Project Abstract

This study investigates how inquiry-based learning (IBL) influences the development of critical thinking skills among high school biology students, employing a mixed-methods design to capture both measurable outcomes and contextual nuances. A quasi-experimental approach was implemented across four public high schools, with two schools randomly assigned to adopt an IBL-focused biology curriculum and two continuing with traditional teacher-led instruction over a full academic term. Quantitative data were collected using a validated Critical Thinking Assessment in Science (CTAS) alongside standardized biology achievement tests administered at pre- and post-intervention intervals. Qualitative data comprised classroom observations, student reflective journals, and semi-structured teacher and student interviews to illuminate processes, experiences, and perceived challenges associated with IBL implementation. Data were integrated through a convergent parallel design, enabling triangulation of results to provide a comprehensive understanding of how IBL shapes reasoning, evidence evaluation, hypothesis formulation, and problem-solving strategies in authentic laboratory and inquiry-based activities. Quantitative results indicated a statistically significant improvement in composite critical thinking scores for the IBL group compared with the control group (p < .05), with effect sizes suggesting meaningful educational impact. Gains were particularly pronounced in areas related to interpretation of data, evaluation of evidence, and the ability to justify scientific conclusions. However, biology content mastery showed only modest but positive gains, suggesting that critical reasoning development occurred alongside, rather than at the expense of, content knowledge. Subgroup analyses revealed greater benefits for students who engaged with the inquiry process through collaborative discourse and structured metacognitive prompts, highlighting the moderating role of instructional scaffolding, classroom culture, and teacher proficiency with IBL practices. Qualitative findings enriched the interpretation of quantitative outcomes. Observations across IBL classrooms described dynamic student-led questioning, iterative hypothesis testing, and collective sense-making during laboratory investigations. Reflective journals demonstrated heightened awareness of cognitive strategies, such as identifying controlling variables, evaluating sources of evidence, and revising claims in light of new data. Interviews revealed perceived increases in epistemic curiosity and tolerance for ambiguity, tempered by initial apprehensions about open-ended tasks and assessment alignment. Teachers reported professional growth through collaborative planning, the need for continuous professional development in designing valid inquiry tasks, and the importance of balancing structure with autonomy to maintain rigor and inclusivity. The study discusses implications for curriculum designers, teachers, and policymakers, emphasizing scalable IBL templates that integrate explicit instruction in scientific reasoning, ongoing formative assessment, and equitable access to inquiry opportunities. Limitations include the quasi-experimental design, potential contamination across schools, and the relatively short intervention window. Recommendations for future research focus on longitudinal tracking of critical thinking trajectories, exploration of digital inquiry tools, and investigation into culturally responsive IBL implementations to sustain and deepen gains across diverse student populations. Overall, findings contribute robust evidence that well-facilitated inquiry-based learning can meaningfully enhance high school biology students’ critical thinking capabilities while maintaining progress in essential content understanding.

Project Overview

What This Project Is About

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A plain-language overview of the topic and what the project investigates.

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The Problem It Addresses

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What problem or gap this project tackles and why it matters to the field or society.

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Objectives of the Project

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1. Assess how inquiry-based learning affects students' critical thinking in high school biology.
2. Compare outcomes between inquiry-based and traditional teaching approaches.
3. Identify which aspects of inquiry activities most improve reasoning and analysis.
4. Provide practical classroom recommendations for implementing inquiry-based strategies.

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What You Will Do Step by Step

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1. Review literature on inquiry-based learning and critical thinking in biology.
2. Design a mixed-methods study with classroom interventions and assessments.
3. Recruit participating classes and obtain consent from teachers and students.
4. Implement inquiry-based activities in selected classes while maintaining control groups.
5. Collect quantitative data using standard critical thinking rubrics and test scores.
6. Gather qualitative data through student reflections and teacher interviews.
7. Analyze data using statistical comparisons and thematic coding.
8. Discuss findings, limitations, and practical implications for teachers.

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Expected Outcome

Expected to show measurable gains in critical thinking for students exposed to inquiry-based learning, with insights into which activities are most effective and how to implement them in real classrooms.