Pre-kindergarten (Pre-K) programs typically improve early academic skills, but those gains too often disappear after children transition to elementary school. At least three hypotheses explain this “fadeout” of Pre-K effects: Pre-K does not focus on the “trifecta skills” that uniquely support subsequent learning and development; the quality of school-age experiences as “sustaining environments” are more important for Pre-K attenders than nonattenders; and kindergarten (K) teachers provide “redundant instruction” by teaching the same skills taught in preschool programs. The present sample included the second year of assessments on 455 children living in rural counties in the Southeast recruited from Pre- K classrooms and the first year of assessments for 246 K classmates without center-based preschool experience. Children’s academic, language, executive function (EF), and social skills were assessed each fall and spring, and the quality of classrooms was measured each winter. Propensity scores weighted the two groups on demographic characteristics. Hierarchical linear models indicated that the Pre-K attenders had higher levels of language, academic, and EF skills than nonattenders at the beginning of K, but those differences significantly declined for academic skills. By the end of K, the Pre-K group showed slightly higher language and EF skills than the nonattenders. Results appeared to support the trifecta skills hypothesis to explain fade-out, with no evidence supporting the differential sustaining environments or redundant instruction hypotheses. Implications and the study’s limitations are discussed. (author abstract)