This is a case study of Benchmark School, which educates 6-to 15-year-olds with a history of school failure. Grounded theory methodology was employed to generate a theory about how the school promotes achievement. Many elements potentially promoting academic achievement were identified, including ones informed by psychological theory and research (e.g., evidence-based literacy instructional practices, strategies instruction, conceptually focused content instruction, many mechanisms to motivate students) but also, selective admissions, human resources (i.e., well-trained teachers, supportive parents, skilled counselors), small class size, and a supportive physical context. The theory that emerges is that many elements must be articulated to remediate struggling elementary students, although some are more important than others.