This research aimed to compare the effect of teaching science through-creative-drama activities and student-centred inquiry-based teaching on the cognitive structures of primary school pupils about the classification of living things. It was designed as an exploratory action research case study and the contribution of both interventions on the cognitive structures was explored. The study was conducted on two fifth grade classes at a public middle school in Turkey during the fall semester of the 2017 year. The experimental group was taught science through-creative-drama activities that were integrated into the unit. While in the control group, student-centred inquiry-based teaching was carried out. Data were collected by pre-post open-ended questionnaires and also word association tests for both groups. It has been revealed that teaching science through-creative-drama activities about the classification of living things topic made a significant contribution to the expansion of the schemas in the cognitive structures compared with student-centred inquiry-based teaching. However, it was difficult for the teacher researcher to control the schemas that pupils came up with, some of which promoted misconceptions.