Genetics remains one of the most conceptually demanding domains in secondary school biology, where persistent misconceptions and abstractness of content often delay meaningful learning. This study examined the effectiveness of Technology-Enhanced Guided Inquiry-Based Learning in strengthening Grade 11 students' conceptual understanding of genetics and reducing persistent misconceptions, employing a mixed-methods approach within a Design-Based Research framework. 50 Grade 11 students participated in the intervention, and a researcher-developed two-tier diagnostic test was administered before and after the implementation of intervention to assess understanding of genetics, while focus group discussions, classroom observation and semi-structured interviews provided qualitative depth. Quantitative analysis revealed a statistically significant improvement in post-intervention performance, t(49) = 5.763, p < .001, with a large effect size (Cohen's d = 0.815), and domain-level analyses confirmed meaningful gains across all areas, with the most notable progress observed in meiosis, gametes, and fertilization. Misconception analysis further demonstrated a considerable shift toward scientifically accurate conceptions following the intervention. Qualitatively, students described the technology-supported activities including simulation videos and animations as engaging and instrumental in visualizing abstract biological processes, while also reporting increased motivation and greater confidence in their learning. Collectively, these findings suggest that Technology-Enhanced Guided Inquiry-Based Learning is a promising instructional approach for promoting conceptual change and reducing misconceptions in genetics, with broader implications for teaching other challenging topics in secondary school biology