We developed various retention programs to support first-year engineering students who start behind their cohort in terms of the Calculus sequence. We focused on increasing the persistence of these students via counseling along with opportunities for students to regain cohort status. Although the retention program evolved, we retained enough of the main elements to a) develop a sustainable retention program, b) draw generalizable conclusions, and c) identify areas for more study. Overall, the assessment data supports our initial hypothesis that catching up academically with one’s cohort is an important part of helping students to persist in an engineering major.