In this manuscript, we have highlighted the importance of dimensional analysis in learning the physical sciences. Our study presents the results of exploratory research that we conducted with baccalaureate students from secondary qualifying schools located in the province of Essaouira in Morocco. We used a questionnaire to collect the data from 123 students. Analysis of this collected data revealed that many students have difficulty mastering the principle and rules of dimensional homogeneity. Therefore, they are not aware that they are making mistakes if they get inconsistent equations. The results of this questionnaire also reveal a set of constraints and difficulties that hinder the learning of physical sciences in secondary qualifying schools. These difficulties are due to insufficient attention to dimensional analysis, whether in the physical sciences curriculum of the secondary education or by teachers of this discipline

Keywords: Dimensional analysis, learning, physical sciences, questionnaire, difficulties