Abstract
This paper presents a study concerning Greek primary school teachers’ (n = 162) ideas about the particulate nature of matter and their explanations of physical phenomena. The study took place during an in‐service training course where the effectiveness of a specially designed intervention was tested. A key feature was an approach based on the concept of a substance and its states rather than “solids, liquids, and gases”. Pre‐intervention, the teachers held misconceptions similar to those of pupils. Also, there seemed to be some relationship between the teachers’ particle model ideas and their explanations of phenomena. Post‐intervention, the teachers’ descriptions and explanations were found to be significantly improved, with almost zero correlation between pre‐ and post‐intervention scores. Implications for science education are discussed.