Several schools and state departments of education are leveraging prevention frameworks such as School-Wide Positive Behavior Support (SWPBS) to address problem behavior in schools, with the ultimate goal of improving academic achievement and producing lasting effects later in life. Much of the research demonstrating the promise of SWPBS has been conducted in the US and focused on near-term impacts, with less exploration of the various international adoptions of the model in other countries, and no studies exploring the longer term impact. This study leverages population-wide Danish administrative registry data (2006--2016) to examine the effect of the Danish/Norwegian adoption of SWPBS on the in-school outcome academic achievement and the out-of-school outcomes enrollment in upper secondary education, unemployment, and crime using a difference-in-differences (DD) design. The DD indicated an improvement in academic achievement in the 2nd and 3d year of implementation at schools likely to have implemented the program.