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Educating the Student Body
2010). Usually, these perceived norms are not in line with healthy or aca-
demically productive behaviors, and cannot be countered by the best efforts 
of parents and teachers. As a consequence, compared with those who used 
recreational media the least, “heavy users” tended to have lower school 
grades and to report that they were getting in trouble “a lot,” unhappy, sad, 
or bored (Rideout et al., 2010). Furthermore, in the face of rapidly advanc-
ing technology, parents and teachers are not always fully aware of the many 
ways in which media and marketing are part of youth’s lives. In addition 
to television and desktop computers, laptops, tablets, and cell phones often 
follow children and adolescents into the school bus, class, recess, and after-
school activities unless such access is limited by policy, providing increasing 
opportunities to be sedentary on school grounds. In 2009 an average of 20 
percent of media consumption, more than 2 hours per day, occurred with 
mobile devices, some of this media use likely occurring on school grounds. 
This figure probably has increased since then. Rideout and colleagues also 
note that children whose parents make an effort to limit media use spend 
less time consuming media, but whether this holds true for limits on recre-
ational sedentarism in the school setting is unknown.
Both recreational and nonrecreational sedentarism in schools need to 
be monitored separately from physical activity. Specific school policies, 
based on updated knowledge of media use, need to focus on decreasing rec-
reational sedentarism in school and integrating prevention of recreational 
sedentarism outside of school into the education curriculum. Because media 
use among youth already is significantly higher than recommended, schools 
should not provide students with increased opportunities for sedentarism, 
such as television sets in classrooms, the cafeteria, or after-school programs; 
access to social networks and recreational media on school computers; or 
the ability to use cell phones anywhere and at any time on school grounds 
or school transportation.
Research is needed to explore sedentarism and media use in schools 
more systematically so that evidence-based school policies to decrease these 
behaviors can be implemented to increase overall, including light-intensity, 
physical activity. In particular, surveys of media use are needed to document 
the amount of recreational sedentarism taking place in the school setting, 
where, in contrast with the home setting, public health policy can poten-
tially be implemented.