The teaching of conceptual understanding is a key objective in the field of science education. But students, on average, do not adequately understand the concepts in a large number of science subjects. This is the case with Ethiopia's students as well. Additionally, conventional instruction is the primary method used by Ethiopian school teachers. This study looked into how tenth grade students' conceptual grasp of heredity was affected by the context-based Relating, Experiencing, Applying, Cooperating, and Transferring (REACT) technique. A convergent embedded experimental design of a mixed-methods approach was employed. One hundred thirty-one students took part in the study. Students in treatment groups 1 and 2 were taught using the REACT technique and conventional instruction integrated with context-based activities, respectively. The pupils in the comparison group received conventional instruction. Semi-structured interviews, observation, and two-tier multiple-choice tests were used to gather the data. Three types of analysis were performed on the gathered data: narrative analysis, one-way ANOVA, and descriptive analysis. The outcome demonstrated that there were significant mean score differences favoring treatment group 2 between treatment group 2 and the comparison group. However, there was no significant difference between the comparison group and treatment group 1. This suggests that, compared to employing the context-based REACT strategy alone or conventional education alone, integrating conventional instruction with a context-based approach has a much stronger positive impact on students' conceptual understanding.