Traditional teaching practices lack student-focused learning, critical thinking, interactivity, creativity and student's engagement in the classroom, which results in boredom and low motivation among students. Moreover, these practices disregard diversification or variability in learners in a classroom. To engage such learners and create better conceptual understanding and interest in the subject, a research study was conducted in which inclusive Universal Design for Learning (UDL) framework infused Project Based Learning (PBL) approach was used. The study was conducted on the students of grade 5 of NUST Creative Learning School (NCLS) Pakistan. On experimental group (grade 5 class), self-made questionnaires (MCQs based) both in pre and post-test was conducted for General Science subject. A quantitative case study was conducted for an in-depth investigation of the case and to understand the process and its effects on students' learning. Data collection tools were predominantly quantitative tools with some qualitative aspects. This study proposed an idea for designing of evidence-based solutions to substitute the traditional teaching methods with UDL infused project-based learning lesson designs. Findings suggest that UDL complained PBL is an effective approach and framework to design adaptable and accessible learning content through research-based testing. It also recommends that such flexible lessons can approach a wide mix of different learner needs, abilities, prior knowledge, and learning styles to increase learning effectiveness and connect learner Knowledge to the real-world application.