The Challenge Me intervention aimed to indirectly involve parents in a school-based intervention, by challenging primary school children to perform physical activity (PA) and nutrition-related activities with their parents. The aim of this study is to gain insight in whether this was a feasible strategy to engage children and parents, especially those of vulnerable populations. An exploratory cross-sectional study design was applied. Four primary schools implemented the intervention. Data consisted of challenges completed (intervention posters) and child and family characteristics (questionnaires and anthropometric measurements). Associations between challenges performed and child and family characteristics were assessed using linear regression analysis. Of the 226 study participants, 100% performed at least one challenge, and 93% performed at least one challenge involving parents. Children who performed more PA challenges were often younger, a sports club member, lived in higher socioeconomic status neighbourhoods, of Western ethnicity and from larger families. Regarding nutrition challenges involving parents, younger children performed more challenges. There was no difference in intervention engagement regarding gender, weight status, PA preference, healthy nutrition preference, or the Family PA and Family Nutrition Climate. Challenge Me has potential in involving parents in a school-based intervention. However, certain characteristics were associated with higher involvement