The Massive Open Online Course (MOOC) “Nature-based climate shelters in Schools: Empowering Teachers for Sustainable Education”, is organised by the COOLSCHOOLS project with the support of Scientix. It is designed mainly for teachers in primary and secondary schools, focuses on the concepts “nature-based climate shelters in schools” (referred to as “NBCSS” in the MOOC), and “urban nature-based solutions” (urban NBS). This document is the official report of the MOOC, providing data and insights on various aspects of the course. It outlines the parties involved in designing and implementing the MOOC, details the course structure and content, describes the dissemination and promotion strategy, and includes participant feedback to assess the course's effectiveness and overall success.