Effects of instruction in phonemic awareness during preschool and/or kindergarten on the metalinguistic development and subsequent reading achievement of young children with disabilities were investigated in this project. The main focus of study combined a longitudinal and experimental design in which 79 preschool children with disabilities received instruction in phonemic awareness during preschool and/or kindergarten and were followed through first grade. These children received 15-minute small group instruction three times a week on phonemic awareness that focused on rhyming, syllable blending, and segmentation. Following treatment, significant effects were found favoring the experimental group on their rhyming skills and their ability to repeat sequences of phonemes. During the second year, 16 children received 2 years of instruction in phonemic awareness in preschool and kindergarten, 17 children received 1 year of instruction in preschool, 6 children received 1 year of instruction in kindergarten, and 15 children did not receive any formal instruction in phonemic awareness skills. No significant differences were found on measures of phonemic awareness. A second replication study, with a new sample of 66 preschool and kindergarten children, also failed to reveal significant experimental group gains. Appendices include the different evaluation forms. (Contains 47 references.) (CR)