Both decoding and encoding skills are needed to build a foundation in reading. Decoding is the process of translating written speech into verbal speech sounds by applying knowledge of letter-sound correspondences. It is the ability to recognize letters, apply their associated sounds, and blend sounds to form words. Encoding is the process of using letter-sound knowledge to write or spell words. Students must understand the various spelling patterns and rules of the Spanish language to correctly construct words. It is important that students demonstrate their knowledge by applying these rules consistently instead of using invented spelling because they may unknowingly write a real word they did not intend.

Students are expected to know that most letters in Spanish correlate to one single sound, like s-/s/, d-/d/, a-/a/. In addition, certain letters when paired together also express one sound. These letter combinations are called digraphs. For example, the letters c + h make the digraph ch that always sound the same (/ch/) regardless of its position in words: choza, hecho, pecho, or cuchara. Another common letter-sound correlation is represented by the digraph rr whose sound is always the same: arroz, correo, carrito, or barrera. Students should begin to understand the potential confusion that may arise when words containing the digraph rr are misspelled. Consider the following example: El caro que compró mi papá es muy bonito. The author probably meant carro (car) instead of caro (expensive).