Abstract

• The main purpose of this study is to identify difficult areas in physics perceived by high school students and to explore the reasons for these difficult areas. The QUA N-QUA L model was used in this study. The results revealed that the two textbooks involve difficult areas for the students with different levels of difficulty and different schools have different difficult areas. However, some content areas are very difficult for almost all of the students from different schools. These areas include vector symbols and addition of vectors, resolution of vectors, motion graphs and their interpretations, freely falling bodies, the turning effect of a force, area expansion and volume expansion, and transverse and longitudinal waves in Grade Ten and the stretching of threads and strings, pressure in a liquid, heat transfer by radiation, the nature of light, and capacitance of parallel plate capacitors in Grade Eleven. Concerning the reasons, the factors related to students, textbooks, teachers, and content influence students' difficult content areas. Among them, the factors related to students and content are the main reasons. The first factor includes disinterest in the lessons, lack of practice to review the lessons regularly, reading the problems carelessly, and lack of mathematical skills. For content-related factors, complex formulae and mathematical concepts are the main reasons. Moreover, prescribing many chapters and language barriers added to the difficulties of the content areas. Based on the results, it can be concluded that the curriculum developer should reflect and analyze the difficult content areas and synchronize them with mathematical concepts. The students should review and practice what they have learned and the teachers should teach the formulae and mathematical concepts involved in these areas clearly. To sum up, the two high school physics textbooks include difficult content areas, and all the students, teachers, and curriculum developers should emphasize these areas.