The current COVID-19 pandemic has generated a series of changes in the daily routines of people, including children and teenagers, in an unprecedented way, which constitutes a global challenge in public health. Social isolation has been a prophylactic measure to prevent the spread of the virus, however, it has generated negative impacts on the physical and emotional health of parents, caregivers, children, and teenagers around the world. Our objective was to evaluate the effects of confinement caused by the COVID19 pandemic at the level of nutritional status, dietary and behavioral patterns of elementary school children and teenagers in a small town of Colombia. Anthropometric parameters such as BMI Z score, waist circumference and waist / height ratio were evaluated in 266 school children and teenagers. A questionnaire with sociodemographic, clinical and lifestyle characteristics and the KIDMED were applied to learn about nutritional aspects. A total of 102 students (38.3%) were classified as having altered nutritional status, being 39 (14.7%) classified with overweight, and 36 (13.5%) with obesity. The prevalence of high adherence to the Mediterranean diet was 12%, 95% CI (0.08-0.16). Overweight was more prevalent in women (26/39, 66.7%) (p = 0.0439), and obesity was discreetly more frequent in men (19/36, 52.7%) (p = 0.7193). We observed a worrying nutritional, dietary and behavioral situation in the children and teenagers studied during the confinement associated with the covid 19 pandemic. This unveils the need to establish strategies and / or public policies in our town that help to promote an adequate biopsychosocial development of the pediatric patient and their family group.