Introduction A management team of a municipal secretary of education had a great concern about the great number of sick leave episodes of their teachers. Sessions aiming a school formative intervention showed the initial demand changed and turned to be the stress at work and its consequences which were perceived by the teachers.

Methods We used the ‘Change Laboratory’ (CL) method to evaluate work conditions, consequences and possible interventions. This method comprises of a set of tools for collaborative learning through experimentation at the workplace, carrying out changes in organisational practices. During 30 sessions, which took place once a week from 08/2015 to 09/2016, participated the elementary public-school teachers, the school management team, safety and occupational health technicians and representatives of human resources department. Individual interviews and meetings were also conducted with all participants.

Results Teachers created a new teaching work model with their daily activities in a comprehensive and collective way. They identified manifestations of tiredness and exhaustion like physical and mental fatigue (‘waking up already feeling tired’, voice disorders, lack of time and willingness to join social and leisure activities). Some of the causes of short term sickness absences were related to the needs to take care of personal and family life. The method allowed the safety service technicians to obtain detailed information of teachers’ work activities and occupational health aspects.

Discussion The CL method provided to the teachers the opportunity to develop leadership and empowerment, such as the discussion of proposals to improve their daily work, relationships with students’ families and with the management school team. Being closer to the reality of how work activities were performed by the teachers, the team of occupational health professional’s experienced new ways of working to improve the organisation and workplace and eventually teachers’ health. Financial support: FAPESP.