Phonological awareness develops overtime beginning in the preschool years. When children enter kindergarten they are generally expected to be able to syllabicate and rhyme words. Children entering first grade are generally expected to be able to blend sounds into words and to isolate the beginning sound in a word.
During first grade the child will learn to isolate the last sound in the word and may begin to segment familiar words into the individual sounds. By the end of second grade a child should be segmenting all sounds into individual sounds and delete beginning or ending sounds and tell the remaining word. The second grade child will also be expected to perform all of these tasks with sound cluster (i.e. ‘st’, ‘ft’, ‘sk’ etc.)