The purpose of this study was to investigate the value of the Metropolitan Readiness Tests in predicting how well students will achieve in the primary grades of elementary school. This information is of special importance to first grade teachers who need help in early inter-class grouping. Also, information concerning the readiness level of children is important in programs which involve ability grouping, such as in non-graded classes. The data for this study were collected from two elementary schools in a large metropolitan school district in Texas. The Metropolitan Readiness Tests scores were secured from test record cards of 110 students who entered first grade in 1963. Subject grades for the students were obtained from permanent record cards. A total of forty-five scattergrams were set up to indicate the position each student occupied in relation to his three test scores and his subject grades in arithmetic, reading, language, spelling, and an average of the three language arts grades. The Pearson product-moment coefficient of correlation and the standard error of the coefficient were computed for each scattergram. The findings of this study seemed to indicate the following conclusions: 1. The Metropolitan Readiness Tests had a definite value for predicting the subject grades of children in first grade. 2. Number Readiness scores had a greater predictive value in first grade than did Total or Reading Readiness scores. 3. The Metropolitan Readiness Tests had a somewhat lesser value for predicting the subject grades of children in grades two and three. 4. In grades two and three, Total Readiness scores had the highest correlation with subject grades. 5. In all three grades, Reading Readiness scores had lower correlations with subject grades than did the other two scores. 6. There was evidence that the lower the Total Readiness score made by children, the larger percentage of such children needed to repeat a grade.