Abstract
Microorganisms are almost ubiquitous, but their small size often makes them difficult for children to conceptualise. This study aimed to assess the impact of an enquiry-based learning intervention on the conceptions of primary school students (ages 9-10) regarding microorganisms. The intervention included practical activities involving the cultivation of microorganisms in Petri dishes, collected from various surfaces. The students’ ideas were gathered through drawings and their descriptions before and after the intervention. The results indicated that, post-intervention, the association of bacteria and viruses with microorganisms increased, demonstrating a deeper understanding of specific types of microorganisms. Additionally, there was an increased awareness of the actions of microorganisms, with students illustrating specific diseases caused by them, as well as recognising their general and specific beneficial effects on humans.

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