<p>Mobile phone technology has gained increasing attention in education; however, its systematic pedagogical application in high school English as a foreign language (EFL) instruction remains underexplored. This study designed, validated, and evaluated a mobile-assisted pedagogical model aimed at enhancing academic enthusiasm, collaborative learning, and English language achievement among high school learners. A sequential exploratory mixed-methods design was adopted. In the qualitative phase, model development was informed by a systematic literature review and expert consultation. In the quantitative phase, the model underwent an expert-based content evaluation, and its instructional effects were subsequently examined using a quasi-experimental pretest–posttest design. The sample comprised 450 10th-grade female students, randomly assigned to experimental (<i>n</i> = 225) and control (<i>n</i> = 225) groups. Instruments included a curriculum-aligned language proficiency test, a collaborative learning questionnaire, and an academic enthusiasm scale. Data were analyzed using descriptive statistics and ANCOVA. Results indicated that the experimental group significantly outperformed the control group in academic enthusiasm, collaborative learning, and English learning outcomes. The findings highlight the potential of mobile-assisted pedagogy to foster motivation, structured interaction, and sustained language learning. The study contributes a validated instructional framework grounded in sociocultural, self-determination, and cognitive load theories. Practical implications include integrating mobile-based activities into lesson planning, providing teacher training for technology-enhanced pedagogy, and ensuring equitable access to digital tools. Future research should examine long-term effects, gender comparisons, and the applicability of the model across diverse cultural and curricular contexts.</p>