This article reports on a study designed to determine if the lowest achieving first-grade students who were identified by their school districts as at-risk for dyslexia can be distinguished from students who have initial reading and writing difficulties but did not present dyslexia characteristics. Thirty-six first-grade students from two different school districts participated in this quantitative study. As part of the study, students were additionally screened with the "Observation Survey of Early Literacy Achievement," the "Feifer Assessment of Reading," and the "Slosson Oral Reading Test--Revised" pre- and post-intervention. Characteristics, effectiveness, validity, and reliability of the assessment tools are included in the discussion. Upon receiving Reading Recovery® as a first intervention, tests indicated very large effect sizes on all measures for all children. Students whose initial screening indicated no dyslexia characteristics made greater literacy gains.