The issue of high school English teachers' selection of teaching media has garnered widespread attention. However, there remain significant gaps in understanding the influencing factors. This paper analyzes the determinants behind teachers' choices using grounded theory and three-level coding, incorporating interviews with educators from both first-tier cities and county towns in China. The findings reveal substantial disparities in resource availability, technological proficiency, and institutional support between urban and rural schools. Urban teachers benefit from abundant resources and robust technical support, which facilitate higher technological proficiency and more effective media integration with curriculum goals. Conversely, rural teachers face challenges with basic access to technology and limited professional development opportunities. Based on these findings, this paper proposes several recommendations to optimize the use of teaching media: enhancing resource availability through increased funding and community support, improving technological proficiency via targeted professional development, strengthening school support with dedicated IT staff and flexible funding policies, and aligning media with curriculum needs to enhance student engagement.