Both study arms occurred during participants' PE class, once a week for 45 minutes for 10 weeks. The ACCELERATION curriculum is designed to improve children's MVPA through learning and practicing new and challenging sport skills in a fun and free-will learning environment that includes not only school but also home environment. The ACCELERATION focuses on introducing the ball to the child at a basic level. Ball mastery is a soccer term that simply refers to the ability to manipulate and play with the ball using all parts of the foot. Since this program was an individual pursuit, not a team endeavor, it was imperative that each student has their own ball during the PE class. The trained undergraduate interns assisted PE teachers to deliver this program to classrooms assigned into the treatment arm. The program trains parents via virtual workshops on delivering the program at home.

Classrooms assigned to the control group received a 45-minute weekly regular PE curriculum for 10 weeks designed to meet state-mandated requirements. For the same research school, a standard PE curriculum was also delivered by the same PE teacher who delivered the intervention curriculum. However, additional training and support were not provided to PE teachers for the implementation of a regular PE curriculum.

A diverse group of key informants (i.e., PE teachers, school athletic department director) and community stakeholders (i.e., professional soccer coaches, Houston Dynamo Academy director) were engaged to help the research team design, modify, and implement the ACCELERATION curriculum to ensure program relevance and appeal. There are several components that described below make our program design both comprehensive and highly adaptable for optimal reach and effectiveness. These include staff development training, parent workshops, on-site and virtual developmental programs, delivery and implementation support from community stakeholders, online resources, family engagement events, equipment donations to improve activity, and on-going support and mentoring services for parents and school-based educators.

MVPA behaviors were assessed objectively with accelerometers (GT3X+ Actigraph, Pensacola, FL). Trained research staff instructed the students to wear the accelerometer on the right hip for 8 days, which allowed participant to adapt to wearing the device and to achieve the study goal of 2 valid wear days per child as consistent with school-based evaluations. A valid day were defined as ≥600 minutes wear time per day. Freedson's age specific cut points for children 6 to 18 years old will be used to determine the intensity of activity.

Sedentary behaviors were assessed objectively with accelerometers (GT3X+ Actigraph, Pensacola, FL). Trained research staff instructed the students to wear the accelerometer on the right hip for 8 days, which allowed participant to adapt to wearing the device and to achieve the study goal of 2 valid wear days per child as consistent with school-based evaluations. A valid day were defined as ≥600 minutes wear time per day. Freedson's age specific cut points for children 6 to 18 years old will be used to determine the intensity of activity.