Teachers at schools for special education observe that their autistic students experience sleep problems that negatively impact their daytime functioning. Although schools are willing to support their students in reducing sleep problems, the implementation of sleep interventions in schools seem to have been unsuccessful. We co-created a school-based sleep intervention. In this paper, we describe which lessons were learned from the school-partnered development of a school-based sleep intervention for autistic students. We will focus on the first three phases of the Centre for eHealth & Wellbeing Research (CeHReS) roadmap: contextual inquiry, value specification, and design. Each phase had specific goals and activities that led to iterative development with the active involvement of relevant stakeholders (future users and professionals). These stakeholders indicated that four factors, with corresponding operationalizations, were important to include in the sleep intervention: limited burden, sense of usefulness, clear guidance and structure, and support cues. The iterative approach with an emphasis on stakeholder participation enabled us to notice possible barriers to the application of the intervention during its development. We could then identify those barriers and apply lessons to adapt the sleep intervention during development, which will likely increase the successful implementation in schools.