In this work, we have analyzed how two Chemistry's teachers developed a planned teaching sequence starting from a STS perspective in their classrooms, trying to identify obstacles and difficulties in engaging this pedagogical practice and taking into account this perspective for science teaching. Lessons were video recorded, transcribed and data were analyzed considering the discursive dynamic established between the teacher and the students. Data analysis showed that possible obstacles to developing didactic activities cannot be associated only with the teacher's practice and experience, but also can be related to aspects, such as: the lack of technical information about the theme studied; continuous improvement related to the technological artifacts; themes requiring a more complex scientific understanding; difficulties in properly putting together scientific concepts and technology implicated with relevant social problems; and difficulty with appropriate didactical sources to approach these specific subjects in science classrooms.
Chemistry teaching; Application of STS approach
