A goal of the St. Paul (Minnesota) Head Start/Public School Early Childhood Transition Demonstration Project is to promote the implementation of developmentally appropriate practices (DAP) in kindergarten through third-grade classrooms through teacher training and the provision of related materials. This project is 1 of 31 sites participating in a federally funded demonstration. The degree of DAP implementation and teachers' efforts to foster parent participation were studied. In addition, the relationship of DAP to student achievement in reading and mathematics, and to classroom behavior (social skills, problem behaviors) was studied, and possible differences in relationships by students' ethnic backgrounds were explored. Two cohorts of children, 248 who entered kindergarten in 1992-93 and 280 who entered in 1993-94, and their families were studied. DAP-related training and classroom materials provided to teachers appeared to have had some impact on project classrooms, although the level of DAP implementation appeared to be quite modest and teachers in the comparison (not DAP) classrooms actually appeared to do more to foster parent participation. There was little evidence of a positive link between DAP and student achievement, but a strong test of this potential relationship was not possible. There was some evidence, although not strong and consistent, for a positive association between DAP and student classroom behavior. (Contains 4 tables, 3 figures, and 14 references.) (SLD)