Secondary School Student's misconceptions about microorganisms. A laboratory sequence to learn about their presence and function

Laburpena

Microorganisms are central to life. However, students have several misconceptions and think of microorganisms primarily as disease-causing hazardous germs, ignoring all the crucial roles they play as well as the benefits we obtain from them. All these misconceptions can significantly hinder the education process, both for students and for teachers. Therefore, the aim of this study was to identify secondary school students’ misconceptions about microorganisms, and to design, implement and evaluate a laboratory sequence that would promote the understanding of concepts as well as students’ critical thinking about the presence and relevance of microorganisms. Students were asked to complete a questionnaire that consisted of open questions, drawings and true/false questions. They also performed three laboratory experiments related to the ubiquity of microorganisms and the antimicrobial effect of different biocides. Our results uncovered many misconceptions related to the presence and functions of microorganisms. However, the didactic sequence proposed in this study enabled students to successfully understand diverse concepts related to microorganisms and promoted students’ critical thinking.