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 in their written products. 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, causing reader confusion.

Students should use their knowledge of prefixes and suffixes to understand that these groups of letters change the meaning of a word when added to its beginning or end. Student should be able to correctly spell words with prefixes and suffixes in their written communications. For example, they should know that the opposite meaning of the word preocupado (concerned) can be made by adding the prefix des- at the beginning of that word: despreocupado (unconcerned). Also, suffixes like -ita or -ito, when added to the end of a word, make the diminutive (small) form of that word. Consider the following examples, casa/ casita, gato/ gatito, mariposa/ mariposita.