Explicitly showing children which letters function as graphemes and what sound value each represents supports the development of orthographic knowledge by making the structure of written words visible and learnable. When children can see how speech sounds are represented in print, they are better able to form precise connections between phonemes and graphemes, which is essential for building stable word representations in memory. Research on orthographic mapping shows that these connections enable words to be stored efficiently in the orthographic lexicon, allowing for rapid and accurate word recognition without reliance on guessing or memorisation (Ehri, 2014). This process depends on the quality of the phoneme–grapheme links that are established, with clearer, more explicit mapping supporting stronger learning outcomes (Kilpatrick, 2015). By highlighting graphemes and their corresponding sound values, instruction reduces ambiguity, supports accurate segmentation and blending, and strengthens the integration of phonological and orthographic information, thereby facilitating the transition from effortful decoding to automatic word recognition and spelling.

Ehri, L. C. (2014). Orthographic mapping in the acquisition of sight word reading, spelling memory, and vocabulary learning. Scientific Studies of Reading, 18(1), 5–21. https://doi.org/10.1080/10888438.2013.819356

Kilpatrick, D. A. (2015). Essentials of assessing, preventing, and overcoming reading difficulties. Wiley.