The present study focuses on students with low academic achievement and the extent of their participation in classroom communication. The aim of this study was to determine how such students were perceived and assessed by their teacher and whether the teacher’s evaluation corresponded with their participation. Repeated semi-structured interviews with a lower secondary school teacher were used to establish how she evaluated her students. The nature and frequency of the interactions between the teacher and the students were examined by structured observations of lessons. The main result of this case study is that the teacher perceived students with low academic achievement differently based on gender. It transpired that she evaluated their participation in communication based on their gender as well. The teacher explained the low achievement of communicative boys based on their difficult family situations and considered them to be distinct. In contrast, the teacher perceived less communicative girls to be quiet and obedient and understood them as possessing no academic skills or potential to improve.