Efeito de uma intervenção didática sobre células fotoeletroquímicas no conhecimento de estudantes de licenciatura : uma possibilidade para o ensino de ciências no ensino básico

Abstract

Reviews like Pisa and the Scientific Literacy Indicator have shown various shortcomings of science education in Brazil. Among which we highlight the lack of teaching methodologies that promote the formation of a citizen able to interact with the world, transcending his ordinary knowledge about it through the science lens. In this context, we have created a didactic sequence (DS) for the teaching of chemistry and physics, which we have associated a unique modification of the experimentation on photoelectrochemical cells proposed by Smestad and Grätzel (1998). DS was offered to students of a Biological Sciences Degree and a Chemistry Degree. The course lasted 12 hours and students answered questionnaires that were applied before and after each of its six stages. Pretest-posttest design allowed a statistical evaluation of DS effect in students' knowledge about the specific concepts of physics, chemistry and other issues, using the nonparametric Wilcoxon test for paired data and the signal test for median. All parameters evaluated showed that DS produced effect causing overall improvement in learning and it also increased students' knowledge. Content analysis (Bardin, 2011) was used for counting and categorization of recording units frequency that were in the questionnaire objective questions, indicating positive and negative characteristics of DS according to students perception. Among the positive features we highlight the dynamic and didactic methodology, which facilitated learning content with hands-on experiment proposals that show easily accessible materials. Negative characteristics mentioned by the students suggest special attention to the classes available time in secondary education and other DS possible adjustments. Thus DS showed favorable characteristics in students knowledge as a partial tool for teachers continuing initial training. Despite students' responses indicate statistically that DS can be adopted in secondary education, its efficiency in teaching process can only be found when applied in elementary school and high school.