The impact of the Family Check-Up (FCU) on family-school engagement was tested in a randomized, controlled trial. Participants were primary caregivers of 321 children. Approximately 87% of families randomly assigned to the intervention agreed to participate and received the intervention. Caregivers in the FCU condition outperformed caregivers in the school-as-usual condition on family-school engagement at home. In addition to outcomes, implementation of the FCU during kindergarten was examined, including family participation in the FCU, dosage, consumer satisfaction, and content of the follow-up sessions when delivered by FCU therapists. Total treatment time averaged at approximately 143 minutes and family therapists had an average of 4.05 contacts with families. The top three topics discussed during feedback and treatment visits were child behavior, positive parenting, and child academic skills. Children's baseline behavior and caregiver perception of the FCU significantly predicted participation in the FCU. Implications for family-centered interventions are discussed. Impact and Implications: Study findings suggest that a family-centered intervention improved caregivers' engagement at and support for learning at home. In addition, caregiver acceptability and child behavior predicted family participation in treatment.