A decomposição de excrementos: uma estratégia de educação científica e ambiental acerca da ciclagem de nutrientes

Abstract

This study aimed to investigate the design of the students and how to approach the decomposition processes, especially fecal material, in basic education, promoting strategies for their use as science and environmental education tool about nutrient cycling. The methodological procedures were organized in four times and the data obtained were analyzed qualiquantitativamente. The first sought to find out how the nutrient cycling of content is covered in basic education, both by Professor of Biology and in the textbook. Data were obtained from the application of a semi-structured questionnaire to teachers about their practice involving the content in question. In parallel was performed the analysis of this content in three textbooks adopted in schools participating in the survey. The third time was applied a semi-structured questionnaire to graduating high school students with questions about their understanding of the decomposition of manure and nutrient cycling. The fourth time was marked by the development of an investigative practice of the excrement decomposition process with a group of 3rd grade of high school. The data showed that, overall, teachers use between three and four classes to address the content, however, they indicated that the main difficulties for and intended between three and four classes for the content of the approach, the main difficulty is the lack of interest students and lack of time to prepare lessons / activities and lack of infrastructure and / or educational materials to address the matter in a practical way. The strategies and the most used teaching resources are data-show, picture, textbook and videos, and only 2 of them make use of practical activities, which are commonly follow-up activities of the decomposition of fruits and building terrariums. In the textbooks analyzed, this content is covered briefly in Ecology unit. The main weaknesses found are the lack of contextualization of biogeochemical cycles with cycling of nutrients, lack of consistency between text and pictures, lack of scales in the practical figures and activities that enhance the approach to this subject. The analysis of students' responses showed that most conceives the notion of decomposition in the disappearance of environmental stool process, but the understanding of the phenomenon is quite superficial, as not named correctly, gave more importance to the participation of physical factors than to living beings and related the disappearance of feces to soil fertilization, although they have not made clear how this would occur. The proposal investigative activity proved to be excellent didactic and pedagogical strategy for teaching and learning of this content, promoting the construction of knowledge through a simple and commonplace phenomenon, allowing the didactic exploration under different aspects that provide cognitive development and student critical.