The purpose of this study was to examine the efficacy of DIBELS Nonsense Word Fluency Scores in the fall of first grade as a predictor of SAT-10 results. A comparison of boys and girls, three ethnic groups (Caucasian, Hispanic, African-American), and three different reading risk groups were examined using multiple regression analyses. Analysis of data from a total of 27,000 participants from a cohort of Reading First schools in 2003/2004 confirmed Nonsense Word Fluency scores in the fall of first grade to be a significant predictor of the SAT-10 reading scores in the spring. Differences found between and within groups were determined very small when Cohen's effect size was calculated. These results support for the use of Nonsense Word Fluency as a valid and useful early literacy assessment tool for determining which children likely need early additional reading instructional support in order to be successful readers.