The ability of students to segment the speech stream into phonemic units and to analyze (make judgments as to same or different) beginning consonant phonemes was assessed at grades kindergarten through third from both high and low socioeconomic groups. Segmentation ability was assessed by the use of a test of actual words in a match-to-sample task, a test of synthetic words requiring a same-different judgment and a task which required deletion of a phoneme from a known word to form a new word. Three prerequisite abilities were also assessed: auditory acuity and understanding of the concepts "same" and "different" with regard to sounds, and "beginning" with regard to sequence of sounds.