The EdResearch for Action "Design Principles Series" focuses on a single program or practice that has been proven to have positive effects on student outcomes. Authors -- leading experts from across the field of education research -- look across many high-quality studies of similar programs to identify the components and conditions that are key to its effective implementation. The "Design Principles Series" helps practitioners adapt and successfully implement an evidence-based program to meet the needs of their target population. This brief discusses online credit recovery as a strategy to help students make up coursework missed during COVID-19. The suggested instruction design includes: (1) blended learning; (2) class size and grouping; and (3) progress monitoring. The brief also outlines strategies pertaining to student selection, student support from school personnel, professional development for instructors, and effective technology.