The Effects of Using English as a Medium of Instruction on School Performance: A Case of Secondary Schools in Nyarugenge District, Rwanda

The English language is powerful in the worldwide arenas of politics, business, and education, with 85% of international organizations utilizing English for official communications. The majority of international organizations also use it as their working or official language. This study presents the results from an investigation into the effects of using English as a medium of instruction on the school performance of selected secondary schools in Nyarugenge District, Rwanda. The objectives of the study were to determine the techniques used for English as a medium of instruction in classrooms, compare the techniques that teachers and learners use to cope with English as a medium of instruction, examine the different ways teachers and learners deal with code-switching and code-mixing within academic activities, and identify the challenges faced by students in Nyarugenge District secondary schools in using the English language. Vygotsky's theory, specifically the cognitive theory, was the main focus of this research. This study used a quantitative method as the primary approach, specifically applying a descriptive research design. The data collected through this method were statistically examined, while qualitative methods were employed for observational and interview-based data. The targeted population of this study was 1,822, and the sample size was 144, calculated using a mathematical formula for learners: (n = N / (1 + N (e)^2)). Research instruments such as questionnaires, structured interviews, and observations were used, and thematic analysis was applied. SPSS was utilized to analyze the collected data. The key findings revealed that English as a medium of instruction plays an important role in school performance. It serves as a bridge between content and school performance, specifically for both students and teachers. Both teachers and students should improve their level of English proficiency for better content delivery, as highlighted by this study. Therefore, schools and educational stakeholders should provide continuous English training for teachers. English plays a significant role in school performance, and it is recommended that it be used more in classroom interactions. Teachers should be encouraged to use English and motivate learners to do so for self-improvement.