Periodic Table of Elements (PTE) is one of the most important tools in chemistry, yet many students still struggle to comprehend it mainly because of the complex concepts it contains like periodic trends, atomic size, atomic numbers, and electronegativity. Previous studies showed ongoing difficulty in understanding and applying these concepts, and the unreliability of traditional teaching methods, yet most focus only on regular students. This study explores the difficulties experienced by STEM students in using the PTE and the effective pedagogical interventions their teachers used. The study uses a phenomenological approach to examine the lived experiences of students from Landy National High School. The participants were five (5) purposively selected Grade 12 STEM students, since the utilization of PTE aligns with their chemistry curriculum. Through in-depth interviews, the researchers identified the difficulties, factors, effects, and the teaching interventions most worked on them. Findings revealed that STEM students continue to experience difficulty in developing a deep conceptual understanding of the periodic table, which affects their overall performance in chemistry. This gap shows that exposure to science subjects alone does not guarantee mastery of foundational concepts. Weak prior knowledge and cognitive overload remain key barriers to meaningful learning. The results indicate that structured visual aids and interactive teaching strengthen comprehension and reduce misconceptions. To improve conceptual understanding, schools need consistent instructional support and active collaboration among administrators, teachers, and parents. Through these, students can build solid foundations and improve chemistry performance.
Villaruel et al. (Fri,) studied this question.