Preferences and Reasoning of 14-15 year-old Students in Relation to Natural or Synthetic Products in Different Contexts: Influence of an Instructional Module

This study addresses the issue of preference for natural versus synthetic products in different contexts, specifically food, medicines, and cosmetics. Participants were 52 students aged 14-15 years from two schools. We analysed the choices and justifications offered by 28 students from one of the schools before and after receiving an instructional module (nine 60-minute lessons over three weeks) focused on decision-making about natural and processed foods. The goal of instruction was not to guide them towards a particular preference (natural or processed foods) but rather to enable them to make well-reasoned and more scientifically-informed decisions. Transfer of learning to the contexts of medicines and cosmetics was also examined. The responses of students in this experimental group were compared with those of 24 comparison students from the other school who did not receive the instruction. Results suggested that the teaching received by the comparison group (based solely on the standard science curriculum in Spain) does not encourage students to abandon assumptions regarding the inherent superiority of natural products, or to justify their preferences in ways that may be considered on-target with respect to the secondary-level science curriculum. By contrast, a shift towards more scientifically informed choices and reasoning was observed following participation in the instructional module. However, there was limited evidence of transfer of learning from the food context to the other two contexts considered. Only in the medicines context did the experimental group show minor improvements at post-test, suggesting that students perceive greater similarity between food and medicines than between food and cosmetics.