Prevalence rates of mental disorders in adolescents, at approximately 17%–50%, are high (Gore et al., 2011; Merikangas et al., 2010), especially for depression with 10-18 % (Busch et al., 2013; Crockett et al., 2020; Kessler et al., 2012). Yet only 23%- 50% use mental health services (Burnett-Zeigler et al., 2012; Essau, 2005; Kessler et al., 2005; Lu, 2020; Lyons et al., 2013). Mental disorders first manifest mostly in childhood and adolescence (Kessler et al., 2005; Merikangas et al., 2010)..Adolescents are therefore an important target group in which to evaluate barriers to professional help seeking, especially because the delay in treatment is longer for early-onset cases of mental disorders than for onset at a later age (Christiana et al., 2000) with an average of 7 to 11 years to the beginning of treatment (Kessler et al., 2005; Wang et al., 2005). Nontreatment leads to chronicity, exacerbation of symptoms, higher impairment of life quality, a lower probability of successfully treating the disorder later, and an increased risk of suicide and self-harm ( Marshall et al., 2005; Merikangas et al., 2010). The estimated likelihood of seeking formal help for personal or emotional problems and suicidal thoughts is relatively low, and adolescents rather prefer informal help sources (Cakar & Savi, 2014; Sawyer et al., 2012; Wilson et al., 2005). Formal help is defined as help from professionals who have a recognized role and appropriate training in providing help and advice, whereas informal help sources (e.g., friends or family) lack a professional background (Rickwood et al., 2009). It has been suggested that young people do not seek formal mental health services because they harbor stigmatizing attitudes toward people with mental disorders, are fearful of seeking help, and have poor mental health knowledge (Aguirre Velasco et al., 2020; Gulliver et al., 2010). Specifically for psychotherapy as a formal help-seeking source, adolescents often report fear because of the unknown setting and procedure as a barrier to access psychotherapy (Pfeiffer & In-Albon, manuscript in preparation). Male adolescents report higher stigmatizing attitudes towards people with mental disorders compared to female adolescents (Chandra & Minkovitz, 2006; Gonzalez et al., 2005; Rickwood et al., 2005), wheras a prior history of help-seeking for mental health problems and familiarity with a person having a mental disorder have a stigma-reducing effect (Calear et al., 2011; Griffiths et al., 2008; Pearl et al., 2016; Pfeiffer & In-Albon, manuscript in preperation). Providing information about mental disorders is one intervention to increase help-seeking behavior, help-seeking intentions, and to enhance positive attitudes towards mental disorders in adolescents (Howard et al., 2019, Rhughani et al., 2011, RIckwood, 2004, Ruble et al., 2013, Salerno et al., 2016). There is evidence that an increase in mental health knowledge is associated with a decrease of self-stigma in the post-evaluation (Young et al., 2013), however, there is a lack of studies evaluating the influence of psychoeducation of psychotherapy and mental disorders towards stigmatizing and self-stigmatizing attitudes using a follow-up evaluation. There is evidence that self-stigma seems to be more resistant to change and more relevant compared to public stigma (Kendra et al., 2014; Nam et al., 2013; Pfeiffer & In-Albon, manscript in preparatoin). Information booklets are a low-cost and easy- accessible intervention to provide information. There is evidence that a booklet for adolescents informing about anxiety disorders and depression increases mental health literacy (Schneider & Borer, 2003; Schiller et al., 2014), but also evidence that they have no significant impact on help-seeking (Sharpe et al., 2016) in a post-assessment. To our knowledge, there is no evaluation regarding the efficacy of a booklet informing about psychotherapy and generalized information about mental disorders, especially with regard to their influence on stigmatizing attitudes. Another medium to increase mental health knowledge are video interventions (Tsoi et al., 2020; Janouskova et al., 2017). Personal contact with people with mental disorders is associated with decreased social distance and lower stigmatizing attitudes (Corrigan et al., 2011; Yang et al., 2013) and remains a gold-standard for anti-stigma interventions (Corrigan et al., 2012; Koller & Stuart, 2016; DeLuca et al., 2020). A video interventions is able to combine education of mental health knowledge and a digital contact with peers sharing their story of having a mental disorder and their way of recovery. Especially with social media, videos in which adolescents communicate about aspects of their mental disorders often provides an easy access to mental health knowledge and a digital contact. Video intervention can equally or sometimes even be more effective in reducing social distance and stigmatizing attitudes than face-to-face interventions (Janouskova et al., 2017). Regarding the evaluation of video interventions there is a lack of evidence: for interventions outside the school setting, where adolescents can watch the video on their own and studies, which looks at long-term outcomes (Janouskva et al., 2017; Salerno, 2016), especially because findings of long term effects of interventions addressing destigmatization and increase of mental health knowledge show mixed results (Aguirre-Velasco et al., , 2020; Schiller et al., 2017).