Sequência didática para trabalhar o tema substância e misturas no ensino de química: um estudo de caso com plantas medicinais

Abstract

It is known that the Science/Chemistry teaching-learning process has been experiencing an educational failure; for many education scholars, it is linked to a decontextualized, non-interdisciplinary science education and the use of traditional metrology (SANTOS; CAMPOS, 2019); thus, this work comes as a possibility to go against this problem, starting from the popular knowledge of medicinal herbs, teas as a starting point for the teaching of Chemistry (mixtures) and to form more and more citizens. In this perspective, the main objective of this work was to develop and apply a didactic sequence involving medicinal herbs and mixtures in 09 classes and, also, in a cooperative way with students, school community and teacher, the construction and maintenance of a didactic site with the cataloging of the main medicinal herbs, most used by the community. First, the Construction Site was built in five stages: i) weeding the land; ii) the implementation of medicinal plants at the construction site; iii) cultivation of the site and preservation of plants; iv) the debate on medicinal herbs and preservation of the construction site; v) discussion about medicinal plants and socialization. Second, at the same time, we analyzed the evidence of learning of a more qualitative than quantitative nature, on the application of this study, Delizoicov (2011), which were in three pedagogical moments: 1) the launch in a dialogic and investigative way of the proposal of study, basic information about medicinal herbs, the initial problematization and a previous questionnaire; 2) the study of medicinal plants and chemistry, mixtures; finally, 3) through a demonstrative experiment, final discussion on the importance of the Medicinal Didactic Site and application of a postquestionnaire. The results of the data addressed in the conclusions reached when confronted between the pre-diagnosis and post-diagnosis where it was noticed that there were significant learning signs demonstrated in the comparative graphs of the results highlighted in the stages developed. Therefore, it is pertinent for a more meaningful teaching, that it starts from the students' daily life, so that they build their knowledge in an active and reflective way.