Abstract
The importance of studying scientific reasoning is crucial for various reasons, ranging from the unsatisfactory outcomes of standardized tests at both national (PLANEA) and international (PISA) levels that govern the quality of learning to the classroom level where there is often a preference for covering a thematic content program rather than encouraging reasoning per se. Due to this, the present article aims to establish the variations in scientific reasoning that occur during the teaching of Physics at the high school level categorized as high marginalization. To achieve this, the Scientific Reasoning in the Classroom Test by Lawson was used, where a pre-test and post-test were administered to two groups, one control and one experimental. In the experimental group, a didactic intervention focused on the use of concepts such as magnitude, unit, and variable was carried out, as teachers had reported that students struggled to relate these concepts, leading to confusion when completing exercises. In contrast, the control group received the class as it is typically conducted. However, the results obtained in the post-test of both groups indicate that there were no statistically significant variations in either the experimental or control group. Despite these results, it was found that students remained in empirical-inductive reasoning during the first part of the Physics course. Therefore, a challenge in educating students under similar conditions would be designing activities that contribute to the transition toward hypothetical-deductive reasoning.