International standardized tests are showing an underperformance of students in geometry and spatial ability relative to other content domains. In this research, we examined the relationship between a teacher's judgment of third- and fourth-grade students' geometry and spatial ability (i.e., grades), three spatial ability tasks (Water-Level-Task, the Rod-and-Frame Test, and the Mental-Rotations-Test), composite spatial ability score, and standardized test scores of geometry and spatial ability. Results showed that this teacher's judgment of a student's geometry and spatial ability was more ambitious than evidence from the other measures. While two of the spatial ability tasks and the composite spatial ability score showed improvement over time, the teacher's judgment of students' geometry, and spatial ability did not show improvement over time. Implications for learning will be discussed.