Prior to randomization a baseline questionnaire will be collected from the teachers and their interprofessional collaborators e.g. educational and psychological counseling services, public health nurses and child welfare social workers. Baseline information on pupils will be based on a survey data collected autumn 2017 and survey data and administrative data for follow-up + 12 and + 24 months. Long-term effects for pupils will be measured after the project has formally ended, up to 4 years after baseline, given that the Norwegian Directorate for Education and Training authorize access and deliver administrative data for follow-up.