['To compare the prevalence of television (TV) watching and of computer/videogame use among high school students (15-19\xa0years) from Southern Brazil between 2001 and 2011 and to identify associated socio-demographic factors.', 'Panel studies were conducted with high school students in the state of Santa Catarina, Brazil, in 2001 (n\xa0=\xa05,028) and 2011 (n\xa0=\xa06,529). TV watching and computer/videogame use were collected using questionnaires.', 'Prevalence of ≥2\xa0h/day of TV watching dropped from 76.8 to 61.5\xa0% and ≥2\xa0h/day of computer/videogame use increased from 37.9 to 60.6\xa0%. In both surveys, those aged 15-16 and those who did not work had higher likelihoods of being exposed to ≥2\xa0h/day of TV watching. Boys, those with higher family income, and those who were living in urban areas had higher likelihoods of ≥2\xa0h/day of computer/videogame use. Older age, studying at night and not working were protective factors to these behaviors.'] Do changes in television viewing and computers/videogames use among high school students in Southern Brazil between 2001 and 2011?