The National Guard Youth ChalleNGe program is a residential, quasi-military program for youth ages 16 to 18 who are experiencing difficulty in traditional high school. The program provides classroom instruction and other structured activities to young people at 40 different sites. The focus of this report is on determining how sites can measure their progress at meeting their overall mission ("to intervene in and reclaim the lives of 16- to 18-year-old high school dropouts, producing program graduates with the values, life skills, education, and self-discipline necessary to succeed as productive citizens"). The report summarizes and documents findings and recommendations from analyses carried out between 2016 and 2020. Sources of data include information gathered during visits to each site, as well as site- and individual-level information gathered yearly over four years. Extant data sets and information from the existing literature are also used as appropriate.