Children of divorced parents have an increased risk of a variety of problems in comparison to children from intact families. Therefore, several intervention programs have been developed directed at children of divorced parents. Yet, empirical data on the effectiveness of these interventions are limited. This study evaluated the school-based, child-directed prevention program Kids In Divorce Situations (KIDS) using a randomized controlled trial. The sample consisted of 156 children randomly assigned at the school level into an experimental (80 children) and control condition (76 children). In addition, 131 mothers and 76 fathers participated in the study. Four assessments took place: a pretest, a posttest, and two follow-up assessments conducted 6 months and 1 year after finishing KIDS. Latent growth analyses demonstrated that the intervention significantly reduced child-reported emotional problems and enhanced child-reported communication with the father and mother-reported communication with the child. The effect sizes ranged from .30-.63. Few moderation effects of gender, time since divorce, or perceived parental conflict on the intervention effects were found. After parental divorce, a limited school-based intervention for children can be efficacious in promoting children’s emotional well-being and parent-child communication.