This study explores how pre-service English teachers demonstrate Technological Content Knowledge (TCK) in designing ZepQuiz-integrated lesson plans and identifies the factors influencing such integration. Using a qualitative descriptive approach, this study analyzed lesson plans (RPP) designed by three pre-service English teachers during their teaching practicum (PLP), complemented by in-depth interviews. Data were analyzed through deductive content analysis based on the TPACK framework (Mishra & Koehler, 2006) and thematic analysis. The findings show that all participants demonstrated TCK, though with varying depth, and that interviews revealed reasoning the lesson plans alone could not capture, such as platform-related constraints. Five factors were found to influence integration: topic suitability, learner characteristics, technological affordances, technology limitations, and other contextual factors, with content-pedagogical judgment consistently prioritized over technological convenience. In all three lesson plans, ZepQuiz functioned as an assessment instrument positioned after content delivery rather than as a medium of delivery, and the analysis is bounded accordingly. The study concludes that lesson-plan-only analysis may underestimate teachers' actual TCK, and that triangulating lesson plans with interviews is necessary to capture their fuller reasoning.