The present study reports on the psychometric properties of the Early Childhood Classroom Observation Measure (ECCOM) in Finnish and Estonian first and third grade classrooms. The observation data were collected from 91 first grade teachers and 70 third grade teachers. Teachers' curriculum goals, teaching experience and the classroom size were measured also. The results of confirmatory factor analysis provided evidence of the three-factor model (management, climate, and instruction) for each dimension—child-centred, teacher-directed, and child-dominated—in both grades. The reliability of the dimensions and sub-scales was good, and some evidence was also found for criterion validity. The findings imply that ECCOM is a reliable and valid instrument for measuring teaching practices in primary school.