This study examined the impact of public elementary principal supervision, and prior prekindergarten coursework/experience on the measured quality of public prekindergarten classrooms and students' developmental outcomes. Pretest-posttest results indicated that students' developmental outcomes significantly improved across six early learning domains in all three of the independent variable principal conditions where (a) principals supervised and had prior prekindergarten coursework/experience or (b) principals supervised and did not have prior prekindergarten coursework/experience or (c) principals who did not supervise their prekindergarten classrooms. However, posttest-posttest results comparing student's developmental outcomes indicated no patterns of significant differences between the three principal conditions. Furthermore, posttest-posttest classroom quality measures were also found to be equivalent. Spearman rank order correlation coefficient analysis indicated no significant relationship between the rank order of the measured quality of classrooms and the rank order of mean classroom gains for student developmental outcomes. Results suggest scale up of prekindergarten classroom at a pace that ensures continued quality program development.