<p>Mathematical word problem performance is a crucial indicator of students’ mathematical abilities, and enhancing mathematical reading comprehension and reading motivation is key. This study examines the impact of a gamified interactive e-book (GIEB) that incorporates metacognitive reading strategies on reading motivation, mathematical reading comprehension, and word problem performance among fifth-grade elementary students. Using a quasi-experimental design, the experimental group learned through the GIEB, while the control group received traditional metacognitive reading strategy instruction. The results show that the experimental group significantly outperformed the control group in reading motivation, mathematical reading comprehension, and word problem performance. GIEB, through strategies such as prediction, monitoring, and reflection, improved students’ ability to analyze information, while its integration of immediate feedback and engaging design effectively stimulated students’ intrinsic motivation to learn, strengthening their interest and focus on learning. This study confirms the critical role of reading motivation and mathematical reading comprehension in word problem learning and supports the application of Self-Determination Theory in education. It provides practical evidence for the use of digital tools to enhance educational quality and aligns with the United Nations Sustainable Development Goal 4, promoting the development of equitable and high-quality education. However, the generalizability of the findings may be limited to Chinese elementary school students, and future research is needed to validate the results in other cultural or educational contexts.</p>