Abordagem do conteúdo de isomeria no ensino médio por meio da modalidade híbrida

Abstract

The content of isomerism has been identified by high school students as one of the most complex and challenging in terms of learning. This is due to the fact that understanding involves abstract analysis of molecular structures and requires prior chemical knowledge such as chemical bonding, molecular geometry, and chirality in organic compounds. In order to minimize this problem, this research work aimed to apply and evaluate the pedagogical approach based on the blended learning model, in order to make the teaching of isomerism more effective, engaging, and enable greater student participation in knowledge construction. Specifically, the contents of constitutional, geometric, and optical isomerism were addressed through a didactic sequence. Among the existing models of blended learning, the rotation model was applied, prioritizing the submodels of flipped classroom and station rotation. As a digital tool to mediate the blended learning, a WhatsApp group called "Isomerism" was created, offering instant messaging exchanges over the internet between students and the teacher. The video lessons provided to students for online study and in the flipped classroom perspective were hosted on the Edpuzzle app. This app allowed the researcher teacher to monitor students' viewing of the video lessons. The activities developed to be implemented in the rotation stations and in the assessments required investigation, planning, management, and a combination of face-to-face and online teaching. The research involved students from the 2nd year of a Chemistry technical course at a State Technical School located in the rural area of the municipality of Igarapava, São Paulo. The content on isomerism was contextualized for students, addressing its importance in the study of organic compounds and its relevance to drug production, which can lead to undesirable consequences such as the case of the drug Thalidomide, causing teratogenic effects in newborns. The teaching of isomerism (constitutional, geometric, and optical) was evaluated through the application of questionnaires containing questions extracted from college entrance exams and administered through Google Forms. The analyses carried out based on the applied questionnaires showed that the hybrid approach provided learning for the students, and knowledge was constructed in a more autonomous, active, and participatory manner. From the evaluation of the hybrid approach applied to the teaching of isomerism, the students had a positive acceptance, although at the beginning of the research activities, there was some difficulty in adopting the flipped classroom activity. Regarding the use of WhatsApp and Edpuzzle apps, the students found them easy to use, readily available, and suitable for the study of isomerism.