The objective of this study was to describe the 3-year outcomes (2011–2013) from the healthy lunchbox challenge (HLC) delivered in the US-based summer day camps (SDC) (8–10 hours day−1, 10–11 weeks summer−1, SDC) to increase children and staff bringing fruit, vegetables and water (FVW) each day. A single group pre- with multiple post-test design was used in four large-scale SDCs serving more than 550 children day−1 (6–12 years). The percentage of foods/beverages brought by children/staff, staff promotion of healthy eating and children’s consumption of FVW was assessed via direct observation over 98 days across three summers. For children (3308 observations), fruit and vegetables (>11–16%) increased; no changes were observed for FVW for staff (398 observations). Reductions in unhealthy foods/beverages (e.g. soda/pop and chips) were observed for both children and staff (minus −10% to 38%). Staff role modeling unhealthy eating/drinking initially decreased but increased by 2013. The majority of children who brought fruit/vegetables consumed them. The HLC can influence the foods/beverages brought to SDCs. Enhancements are required to further increase FVW brought and consumed.