Background: Social isolation secondary to the pandemic can predispose the population to mental health issues in the future, especially teenagers. The Depression, Anxiety, and Stress Scale (DASS) is a valuable self-report scale since it may be used to screen for anxiety, depression, and stress in one questionnaire. In the last years, it has been observed effective in detecting these symptoms in teenagers.

Aims: Identify the prevalence of depression, anxiety, and stress in high school students during the COVID-19 pandemic This is an observational cross-sectional study.

For this study, the validated Spanish version of DASS-21 will be used. Qualitative variables will be evaluated through central tendencies, such as mean, standard deviation, and frequencies. The inferential analysis of categorical variables will be performed using the chi-squared test, analysis of variance (ANOVA), or Kruskal Wallis test as appropriate. For quantitative variables, Student's t-test or Mann Whitney U test will be performed depending on their distribution.

Inclusion Criteria:

• Adolescents from 14 to 22 years old.
• That they voluntarily agree to participate, and consent.

Exclusion Criteria:

• Adolescents with depression, anxiety, and stress disorders previously detected
• Patients in psychiatric treatment for depression, anxiety, or stress.
• Participants who don´t consent to participate

Adolescents from 14 to 22 years old with an average age of 16 years are high school students.