This thesis examined the relationship between the level of endorsement of developmentally appropriate practice (DAP) by 14 second-grade teachers and the construction of self-concept of children in their classrooms. Teachers were given the Primary Teacher Questionnaire, a beliefs scale that assesses the level of endorsement of DAP, and were classified as having a higher or lower endorsement of DAP. Four children were randomly selected from each of the 14 classrooms and given the Self Description Questionnaire I, a multidimensional measure of self-concept in children ages 5 to 8 years. Results indicated that children in classrooms of teachers who had a high level of endorsement had higher academic self-confidence scores than children in classrooms of teachers with low levels of endorsement. The study also found that teachers who had been teaching for longer periods of time had lower levels of endorsement of DAP than those with less teaching experience. (A copy of the Primary Teacher Questionnaire is appended. Contains 41 references.) (Author/MDM)