The ultimate goal of reading is to comprehend written text, and this goal can only be attained if the reader can decode written words and understand their meanings. The science of reading has provided compelling evidence for the subskills that form the foundation of decoding. Decoding words requires understanding of the alphabetic principle and letter-sound, or grapheme-phoneme, correspondence. In the first year of formal schooling (kindergarten), this same understanding is also required for young learners who are learning to write the letters of the alphabet. In this article, we examine the effectiveness of a handwriting intervention, Write Start-K, that emphasizes the recall, retrieval, reproduction, and repetition (the 4Rs model) of grapheme-phoneme relations. We conducted a two-group, pre/posttest study at two Australian schools across four kindergarten classes (n = 77 students). One school received the intervention, and the other continued with standard teaching. Participants (mean age = 5 years 8.45 months, standard deviation = 4.18 months) at both schools were assessed at baseline, immediately after the eight-week intervention period, and at 12 weeks following the end of the intervention (follow-up). We used linear mixed models to determine the statistical significance of effects over three time intervals. We identified statistically significant Group x Time effects for letter name knowledge and word reading, whereas changes in letter sound knowledge and nonsense word-reading fluency approached statistical significance. These results indicate that a handwriting intervention, incorporating repeated practice in recalling and reproducing letter forms, had a statistically significant impact on early reading skills.