Classwide supports were used to increase children's early literacy skills for Head Start morning and afternoon classrooms within a preschool Response to Intervention (RtI) model. Support included interventions to improve child outcomes for letter naming fluency (LNF) and teachers' instructional and managerial variables. Targeted activities included circle (a group instructional activity) and center times (also instructional time with children's choices about activities). Support for teachers included adding a "letter of the week" activity with active responding and other literacy activities and providing direct feedback to teachers about classroom managerial interactions. Results show positive classwide improvements for LNF, an increase in the prevalence of instruction, and improvements in positive and instructional managerial methods. Social validity appraisal indicated that the support methods were highly acceptable. C 2010 Wiley Periodicals, Inc.