Critical features of professional development programs: Comparing content focus and impact of two large-scale programs

By comparing two large-scale professional development programs' content and impact on student achievement, we contribute to research on critical features of high quality professional development, especially content focus. Even though the programs are conducted in the same context and are highly similar if characterized according to established research frameworks, our results suggest that they differ in their impact on student achievement. We therefore develop an analytical framework that allow us to characterize the programs' content and delivery in detail. Through this approach, we identify important differences between the programs that provide explanatory value in discussing reasons for their differing impacts.