A study of teachers’ usage of vague terms in the geometry classroom

The purpose of this study was to investigate the relationship between teachers’ usage of vague terms in the mathematics classroom and student achievement. The teacher clarity variable was evaluated through the frequency of vague terms used by teachers in 13 secondary geometry classrooms. Student achievement was measured by the Howell Geometry Test. The sample was 249 students. The results supported the assumption that there is a relationship between teacher clarity and student achievement in the mathematics classroom.