State law recommends recess.
Alaska Statutes 14.30.360 Health education curriculum; physical activity guidelines.
(c) ...a school district shall establish guidelines for schools in the district to provide opportunities during each full school day for students in grades kindergarten through eight for a minimum of 90 percent of the daily amount of physical activity recommended for children and adolescents in the physical activity guidelines by the Centers for Disease Control and Prevention, United States Department of Health and Human Services. The time provided for physical activity under this subsection may include physical education classes and opportunities for unstructured physical activity, such as recess.
STUDENT NUTRITION AND PHYSICAL ACTIVITY BP 5040 (a)
This document addresses frequency of recess for elementary students.