This brief presents a method for predicting the impact of school closures on average ACT® test scores. The purpose is to illustrate a methodology and major conditions that should be considered in predicting aggregate ACT scores when school closes prematurely and learning and testing are disrupted. Across three scenarios examined herein, the impact on academic achievement was predicted to be between -0.71 and -0.31 Composite score points. The predictions are based on a number of assumptions and may not be applicable in every case. ACT can assist state and district partners in applying and interpreting this or similar models to predict the effect of COVID-19 on learning and performance within their local context.