The investigators long-term goal is to increase the number of Summer Day Camps (SDC) that meet the National Afterschool Association Healthy Eating and Physical Activity (HEPA) Standards. The objective is to evaluate the effectiveness of a multi-component intervention designed to increase children's PA levels and improve the quality of lunches and snacks children consume in SDCs. The HEPA intervention is designed to target children, parents, staff, program leaders, and the SDC environment and uses a train-the-trainer model with SDC leaders to train their staff to deliver and integrate the intervention into routine practice. In the proposed study, the investigators will evaluate these HEPA strategies, using a 4-year randomized controlled trial with 20 SDCs. An important feature of the study will be the evaluation of maintenance of the intervention after the removal of research support (e.g., training, boosters) during the final year, as well as costs associated with implementation.

The investigators hypothesize that intervention SDCs will achieve significantly greater increases in HEPA, compared to control SDCs. The investigators expect the study to support the cost-effectiveness and maintenance of our strategies for promoting HEPA that will facilitate SDCs meeting newly-established HEPA standards for this setting.

The investigators aim to:

Evaluate the impact of the HEPA interventions on: 1.) The proportion of children meeting the PA Standard (i.e., ≥60min MVPA/d) while attending summer day camp; 2.) The proportion of foods (e.g., fruit, vegetable, water) children and staff bring and consume at the summer day camp that meet the HE Standards; and 3/) Changes in children's age-sex specific BMI percentile from the start to end of summer

Evaluate the cost-effectiveness of the HEPA intervention

Evaluate the maintenance of the HEPA intervention in summer day camps

Inclusion Criteria:

• Summer Day camps will be eligible if:
• They operate for at least 10 weeks during the summer
• They do not have any primary focus such as sports, art, or tutoring (must be a general camp)
• Enrollment is at least 40 campers
• Operation hours are at least 8 hours.

Exclusion Criteria:

• Children will be unable to wear an activity monitor if experience any physical and/or orthopedic impairment that limits the child's ability to participate in regular PA (e.g., wheelchair user)