A study tested the effects of activity-based phonological instruction (rhyming, blending, segmenting) on the phonological skill development and reading and writing outcomes of kindergarten children, 31 with and 57 without disabilities, and 19 children repeating kindergarten in regular and self-contained classes in a large urban school district. The ethnic distribution in the school district was 52% Black American, 46% Caucasian, and 2% other. Five classroom teachers in the treatment received 10 inservice training sessions spaced over the school year, and implemented from 98-280 activities during the 6-month treatment. Outcomes for treated children were compared with those of children matched for type (regular or repeating kindergartners, or children with mild disabilities) in classrooms using the same background prereading curriculum. Results suggested that intervention delivered by kindergarten teachers can be an effective way to improve the literacy outcomes of children with a broad range of abilities. As a feasibility test, this study suggests that classroom teachers can improve the phonological skills of their students prior to formal teaching instruction; but to make large and lasting differences in the reading trajectory of children with disabilities, instruction may need to be much more intense than that delivered to large classroom groups. (AA)