This research paper aims to demonstrate the students’ understanding of mathematical function through Desmos. As an educator, the task of finding ideas to convey knowledge effectively to students in this age of technology is challenging. The importance of implementing PBL is essential to maintain interest and interact during the learning process while preparing them for challenges in this modern world. For a larger class size, PBL will help the students for a better leaning process by doing activities that most students can participate in and express their ideas. In this study, a total of 127 foundation students were involved in doing the simulation by using Desmos, a free web-based software as part of their 8-week project assignment. The students were asked to combine and relate the polynomials and piecewise function to design two roller coaster tracks by using Desmos. The results are spectacular. With great teamwork and continuously seeking guidance from the instructors, students were able to show their creativity by presenting the end-product. © The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd. 2024.