The relationships between teacher ratings and standardized achievement tests as measures of student progress are investigated. Initial teacher ratings of pupils in grade 3 and subsequently in grade 6, were contrasted to scores obtained on the Metropolitan Achievement Test (MAT). It was found that a teacher's rating does not provide the same information about the pupil's level of achievement as do the MAT scores. Although a relationship between the two measures was found, the degree of relationship depended upon what areas the teachers had rated. An examination of the data revealed a consistent pattern in the relationship between various subsections of the Teacher Rating Questionnaire and the MAT, the discrepancy scores, and the I.Q. scores. Teacher ratings of performance were much more closely related to these measures than were their ratings of pupil adjustment and creativity. Despite differences among teachers and among classes, as well as the development in the pupils' characteristics from grade 3 to grade 6, there was a reasonable level of agreement among teachers' ratings of student performance. The data supports the conclusion that teachers' ratings of academic achievement are an important and dependable adjunct to the use of standardized achievement tests. The development of the instrument is described briefly and copies of two versions are appended. (Author/AG)