The study investigated the effects of stimulating self-regulated learning (SRL) in hypermedia to support mathematical literacy of lower achievers students compared to higher-achiever students. We examined seventh-grade students (n = 64) who were exposed to a self-directed hypermedia environment either supported by SRL with IMPROVE self-questioning (the H_SRL group) or receiving no direct SRL support (the H_NS group). Mathematical literacy was investigated with (a) authentic problem-solving tasks (Programme for International Student Assessment (PISA). Literacy skills for the world of tomorrow: Further results from PISA 2000. Author, Paris, 2003) and (b) online discussion for SRL processes (cognitive, metacognitive, motivation, and social feedback). Findings indicated that the H_SRL intervention led to more significant gains than the H_NS group in mathematical literacy for students of varying ability levels (lower and higher achievers). In addition, the benefits of H_SRL persisted in online discussion feedback. These effects were particularly beneficial for the lower achievers. This study offers potential contributions to theoretical research examining the role of SRL support in hypermedia for enhancing mathematical literacy and SRL of lower-achiever students.