The current study follows a sample of lower skilled language minority (LM) and native English-speaking (non-LM) students who participated in an efficacy trial of a kindergarten phonics-based intervention. Follow-up procedures allowed 93% of the original sample to be retained for simple treatment effects modeling (N = 78 LM and N = 59 non-LM) and 72% to be retained for classroom instruction modeling (N = 62 LM and N = 44 non-LM). Simple treatment effects on longer term outcomes were detected on word reading, spelling, and comprehension outcomes for LM students (approximate effect sizes averaged 0.27); comparatively, treatment effects for non-LM students were detected on all outcomes, including fluency (approximate effect sizes averaged 0.54). Instructional model results showed that greater time in Grade 1 word study instruction and Grade 2 meaning instruction was associated with higher reading scores for LM students at the end of second grade, irrespective of experimental condition. For non-LM children, greater time in Grade 1 meaning instruction was connected with higher reading scores at the end of Grade 2, irrespective of experimental condition. Finally, kindergarten intervention effects tended to be greater for both LM and non-LM students who received more Grade 1 word study instruction and more Grade 2 meaning instruction. Limitations and practical implications are discussed. (Contains 7 tables and 3 figures.)