Previous efforts to involve parents in implementation of childcare-based health promotion interventions have yielded limited success, suggesting a need for different implementation strategies. This study evaluated the efficacy of an enhanced implementation strategy to increase parent engagement with Healthy Me, Healthy We. This quasi-experimental study included childcare centers from the second of two waves of a cluster-randomized trial. The standard approach (giving parents intervention materials, prompting participation at home, inviting participation with classroom events) was delivered in 2016–2017 (29 centers, 116 providers, and 199 parents). The enhanced approach (standard plus seeking feedback, identifying and addressing barriers to parent participation) was delivered in 2017–2018 (13 centers, 57 providers, and 114 parents). Parent engagement was evaluated at two levels. For the center-level, structured interview questions with providers throughout the intervention were systematically scored. For the parent-level, parents completed surveys following the intervention. Differences in parent engagement were evaluated using linear regression (center-level) and mixed effects (parent-level) models. Statistical significance was set at p < 0.025 for two primary outcomes. There was no difference in parent engagement between approaches at the center-level, β = −1.45 (95% confidence interval, −4.76 to 1.87), p = 0.38l. However, the enhanced approach had higher parent-level scores, β = 3.60, (95% confidence interval, 1.49 to 5.75), p < 0.001. In the enhanced approach group, providers consistently reported greater satisfaction with the intervention than parents (p < 0.001), yet their fidelity of implementing the enhanced approach was low (less than 20%). Results show promise that parent engagement with childcare-based health promotion innovations can positively respond to appropriately designed and executed implementation strategies, but strategies need to be feasible and acceptable for all stakeholders.