The goal of this clinical trial is to learn if different formats of a school-based psychosocial support training program can improve teachers' ability to recognize and respond to students' mental health needs. The study will include teachers working in public schools in Brazil.

The main questions it aims to answer are:

1. Do teachers who receive the training improve their knowledge on how to better to identify and support students with mental health difficulties?
2. Do different formats of training (in-person, online, or self-paced) and the presence of supervision lead to different levels of improvement in this knowledge, in attitudes related to mental health, and helping behaviors?

Researchers will compare five versions of the program (in-person, online, and asynchronous formats, with or without supervision) to see which approach is more effective, acceptable, and feasible.

Participants will:

1. Take part in a training program delivered either in-person, online, or through self-paced materials;
2. In some groups, attend additional supervision sessions to discuss real-life cases;
3. Receive brief follow-up materials through mobile messages after the training
4. Complete online questionnaires at multiple time points (before the training, during the program, after completion, and at follow-up).

The study will measure changes in teachers' knowledge, attitudes, and behaviors related to supporting students' mental health, as well as satisfaction with the program and its feasibility for large-scale implementation.

Inclusion Criteria:

School-level inclusion criteria:

• Public schools from the state education system of Rio Grande do Sul, Brazil, serving students in "Ensino Fundamental" and "Ensino Médio" (equivalent to grades 1-12), and belonging to "Polo 1", an administrative grouping defined by the Rio Grande do Sul State Department of Education that includes the following Regional Education Coordinators (Coordenadorias Regionais de Educação [CREs]): 1st, 2nd, 11th, 12th, 27th, and 28th CREs;
• Schools with 10 or more teachers on staff;
• Schools with a complete school management team, defined as having all three core management roles in place.

Participant-level inclusion criteria (teacher level)

Participating teachers must meet all of the following criteria:

• Teachers currently working in participating public schools;
• Able and willing to participate in all stages of the intervention and scheduled assessments;
• Provide informed consent prior to participation

Exclusion Criteria:

School-level exclusion criteria:

• Schools with fewer than 10 teachers on staff;
• Schools without a complete school management team;
• Youth and Adult Education Centers (Núcleos de Educação de Jovens e Adultos [EJA]);
• Schools that began operating as full-time schools in 2026;
• Schools not belonging to Polo 1 of the state education system of Rio Grande do Sul;
• Schools that do not serve students in grades 1-12

Participant-level exclusion criteria

• Not currently working as a teacher in a participating public school;
• Unable to participate in the training in the planned date for the specific school the teacher works at;
• Decline or are unable to provide informed consent

De-identified individual participant data underlying the results reported in this study (including data dictionaries) will be made available to qualified researchers.

Data will be shared after publication of the primary results, upon reasonable request and subject to approval by the study investigators. Requests will be evaluated based on scientific merit, feasibility, and ethical considerations.

Data will be provided in a de-identified format to ensure participant confidentiality and compliance with applicable data protection regulations.