“…First, student attrition in both regions, but particularly the Southeast, occurred either because students stopped attending or participating in virtual instruction or participated so infrequently, they could not maintain progress in the GSC App consistent with the class implementation schedule. Although previous sensitivity analyses on student outcomes using the GSC App suggested confidence in intervention effects despite student attrition (Mazzotti et al, 2023; Shogren, Mazzotti, Hicks, et al, 2023), because unexplained attrition can bias reported effects, future research should examine how to support teachers and students in staying on track with their implementation schedules and replicate the current analyses to assess potential differences. Second, due to the compounding limitations of small sample size and 12 possible pathways across Phase 3 GSC App lessons, the average ratings of student responses to Phase 3 activities could not be adequately explored in this analysis.…”