This study compared the rate of reading gains of first and second grade students before and after implementation of the Direct Instruction reading program, Reading Mastery. The intent of this study was to determine if reading instruction with Reading Mastery would accelerate at-risk students’ acquisition of reading skills. Results indicate that both first and second graders demonstrated significant differences in rate of reading gain before and after implementation on the Total Reading measure of the Woodcock Reading Mastery Test; additionally, rate of gain on the Word Attack subtest for first graders and Word Identification subtest for second graders were significantly greater following implementation. (Copyright © 2011, National Institute for Direct Instruction (NIFDI). All rights reserved).