Many students who struggle to obtain the alphabetic principle are at risk for being identified as having a reading disability and would benefit from additional explicit phonics instruction as a remedial measure. In this action research case study, the research team conducted two experiments to investigate the effects of a color-coded, onset-rime, phonics-based intervention on the word reading behaviors of four first-grade students. In each experiment, the research team used a multiple probe across two participants design to investigate the effects of the intervention. The findings suggest that all of the participants' word reading performance on instructed words improved after instruction when compared with baseline performance, and they were able to maintain these gains 2 weeks postinstruction. However, only two of the participants' performance increased postinstruction on their word reading of uninstructed words with the same rime pattern as instructed words. A discussion of the results and suggestions for implementation are included.