<p style="text-align: justify;">The mathematical literacy ability of Indonesian pupils is still relatively low, as indicated by Indonesia's score of 379 for mathematical literacy in PISA 2018. Paying attention to the learning process such as the teaching materials used in learning, is one of ways to increase mathematical literacy skills. To strengthen students' mathematical literacy skills, it is great for building qualified mathematics teaching materials with the nuances of science, technology, engineering, and mathematics (STEM) which are supported by the information and communication technology (ICT)-assisted Preprospec (Prepare, Problem Solving, Presentation and Conclusion) Learning Model. The research method used in this study is research and development (R&D), with the main reference of 4D-model development by Thiagarajan, whose stages are limited to define, design, and develop. The results showed that the feasibility test on teaching materials obtained the total average percentage of validator I to validator V, respectively, 90.19, 95.45, 93.90, 91.95, and 97.95 with very eligible criteria. It is easy to understand by students with a readability score of ρ = .109 > α = .05 or Cochran's Q = 13.091, and it can improve students' mathematical literacy skills, as evidenced by the Wilcoxon test and a gain normalization result of 485.</p>