نسرین مهرورز باهمبری

Drawing on the team-teaching model of multiple instruction, this study aimed to investigate the impact of team-teaching on the English language achievement of Iranian high school students. The study employed a sequential explanatory mixed-method design, consisting of two phases for data collection and analysis. In the quantitative phase, 40 male and 40 female students aged 16-18 were conveniently sampled from tenth-grade high schools in Lahijan, Iran. They were divided into two experimental and two control groups. The experimental groups received instruction using the team-teaching model, while the control groups received traditional instruction. Data analysis was conducted using one-way ANOVA, which revealed a statistically significant improvement in the performance of the experimental groups compared to the control groups. Due to gender differences, the results showed no significant disparities in the outcomes achieved by male and female students. In the qualitative phase, the same participants from the experimental groups were asked to provide open-ended responses regarding the advantages and disadvantages of the team-teaching method, using a questionnaire developed by Jones and Harris (2012). The responses were carefully examined using open coding techniques, and common themes were identified through systematic comparison of the codes. The findings indicated that team-teaching offered a wide range of benefits. Considering gender differences, it was evident that male participants perceived the benefits of the team-teaching model to outweigh the drawbacks more than their female counterparts. These findings have pedagogical implications for Iranian teachers and theoreticians in the field of English language instruction.