Nearly one in five children are obese, and disparities in overweight and obesity between children from low- and middle-to-high-income households persist despite a multitude of school-based interventions. The structured days hypothesis posits that structure within a school day plays a protective role for children against obesogenic behaviors, and, ultimately, prevents the occurrence of excessive weight gain, thus, past school-based efforts are misplaced. This study will provide access to healthy structured programming via vouchers to afterschool programs and summer day camps during two "windows of vulnerability" (ie afterschool and summer) for low-income children.

Despite the public health field's best efforts, disparities in overweight and obesity (OWOB) prevalence between children (6-11) from low- and middle-to-high-income families persist. Previous interventions to address disparate rates of childhood OWOB have focused almost exclusively on school settings. Given that disparities in OWOB persist, current school-based efforts may be misplaced because children engage in more unhealthy behaviors outside of school (e.g., afterschool during weekdays and during the summer). The structured days hypothesis posits that a structure within a day, defined as a pre-planned, segmented, and adult-supervised compulsory environment (like a school day), plays a protective role for children against obesogenic behaviors, and, ultimately, prevents the occurrence of negative health-outcomes, such as, excessive weight gain. Essentially, the structured days hypothesis draws upon concepts in the 'filled-time perspective' literature which posits that time filled with favorable activities cannot be filled with unfavorable activities. There are at least two "windows of vulnerability" for children outside of the school day. These critically important windows include the hours immediately following school (i.e., 3-6pm school days) and the 10 weeks of summer vacation. Programs that can provide a healthy structured environment and prevent unhealthy weight gains exist for both of these time periods (i.e., afterschool programs and summer day camps). Unfortunately, these programs are too expensive for children from low-income families to attend. Thus, this study will rigorously test the impact of providing access to existing, community-operated afterschool and summer programs on weight status (i.e., BMI z-score) and obesogenic behaviors (i.e., physical activity, screen use, diet, and sleep) of elementary children from low-income households. The study will employ a 2x2 full factorial design. The two factors will be access, through vouchers, to structured programming. The four groups will be a no treatment control, afterschool program voucher only, summer day camp voucher only, and vouchers for afterschool and summer day camp combined. The study will accomplish the following specific aims: AIM 1 (Primary): Compare changes in z-BMI among children in the no treatment control, afterschool only, summer camp only, and afterschool and summer day camp combined groups. AIM 2 (Secondary): Compare differences in obesogenic behaviors during the school year and the summer among children in the no treatment control, school only, summer camp only, and afterschool and summer day camp combined intervention groups. AIM 3 (Secondary): Evaluate the cost-effectiveness of delivering the afterschool only, summer camp only, and combined interventions. This study is significant because nearly one in five children are obese, and disparities in OWOB between children from low- and middle-to-high-income households persist despite past school-based interventions. This study is innovative because it represents one of the first attempts to provide access to healthy structured programming during two "windows of vulnerability" for children outside of the school day. Should the proposed intervention strategy prove effective it has the potential to mitigate disparities in OWOB prevalence.

Inclusion Criteria:

• k-4th grader in a partner school
• eligible for free and reduced price lunch (a widely recognized indicator of
• socioeconomic level and poverty status)
• parent that indicates "yes' on an informed consent document for participation in the study

Exclusion Criteria:

• Diagnosis of an intellectual disability, such as Down Syndrome, Fragile X, Fetal Alcohol
• a physical disability, such as wheelchair use, that prevents the ability to ambulate without assistance.
• Families who plan to enroll their children in a summer camp or after school program or relocate (i.e., move) during the 14-month period that they participate