SHAPE America -- Society of Health and Physical Educators has targeted youth physical activity (PA) as 1 of its 4 goals within the 50 Million Strong[TM] campaign. Only 27.1% of youth met the target of all students (preK-12) participating in at least 60 min of PA that increases their heart rate enough to breathe hard at least some of the time for 7 days/week. Thus, improvements for child and adolescent engagement in PA need to be made now through 2029 and beyond. The need for these improvements warrants research related to PA and youth. We present a plethora of research questions within 3 general areas: PA and school PA programs, PA and sedentary behavior measurement, and PA and social justice imperatives. Each question is framed within the social-ecological framework levels of learning, opportunity, policy, and population health.