Contextualizando o ensino de química com o tema cosmético por meio de uma proposta de sequência didática

Abstract

Cosmetics are preparations made up of synthetic or natural substances and are used in external parts of the human body. They are widely used for embellishment.The aim of our research was to develop a didactic sequence involving cosmetics to introduce organic functional groups in a 3rd year class at “Escola Estadual de Ensino medo e Técnico Frei Plácido in Bagé. Our idea was to divide the topic into three stages that were applied during 8 hours.In the first stage, there was a short introduction in cosmetics and organic functional groups, we applied a questionnaire and afterwards a short summary relating cosmetics to chemistry was discussed in class. Afterwards during the second stage, organic functional groups containing nitrogen and/or oxygen were revised and examples of compounds present in cosmetics were presented. At the end of each class we discussed examples and explained the problems associated with their use in cosmetics. In the final stage we tested the students progress by applying a short test over the content presented. After the conclusion of our work we could observe that our approach induced curiosity among the students by relating a subject from their day-to-day life to organic chemistry and that they showed a significant increase of knowledge comparing the results of the questionnaire and test before and after the classes.