Abstract:

In this paper, we examine the epistemic knowledge performed by high school students in a task, set in an alimentary emergency, that requires them to engage in inquiry and argumentation practices. This study is framed in the disciplinary perspective of epistemology of science, which considers shared epistemic commitments, as the relation between causal explanations and observations, for many disciplines, but also takes into consideration the differences between them. This proposal is part of a larger study on students' engagement in epistemic knowledge and scientific practices in the context of food safety carried out in secondary education.

The task requires students to design an experiment to find the cause of a real food emergency, selecting the samples for the experiment, including an adequate human sample among those available (saliva, blood, stool...) and predicting which strain of bacteria is causing the illness. Students have to provide a justification for each choice, and the information they receive to do so is a chronology describing the actual events following the outbreak, a medical report and information on the different strains of E. coli bacteria (what type of cells they may affect, what are the usual symptoms…). After the design phase, students receive a chronology that narrates the actual events after the discovery of the cause of the outbreak. In this case, students have to assess if the government's action was correct and why, and whether there are differences with the WHO protocol for alimentary emergencies or not.

The participants are students from 10th grade (15-16 years old) and 11th grade (16-17 years old) attending Biology lessons and working in small groups. This task was implemented in one 50-minute session.

For the data analysis, the session was recorded, later transcribed, and coded in terms of the epistemic disciplinary aspects considered by students during their conversations while solving the task. After several iterative cycles of analysis carried out between the two authors, two rubrics were developed in interaction between data and literature. The first one examines the epistemic aspects involved in the design phase and it is related to the inquiry practice, whereas the second examines the epistemic aspects used in the assessment stage, which is related to the joint practices of argumentation and inquiry.

The general results indicate that only a few epistemic aspects, such as ‘students recognize that the samples chosen for an experiment have to be representative’, usually common to all groups, are identified in students’ conversations while others, such as ‘students recognize that the experiment needs to be reproducible’ are completely missing. Implications for design are discussed.

Keywords:

Epistemic knowledge, food safety, inquiry, argumentation, high school.