As participants had a large degree of freedom to design their strategies, the variability allows several preliminary lessons to be drawn. After discussing the professional development measures implemented by teams participating in the project, it highlights the main lessons from the teacher professional development plans implemented by the country teams to support participating teachers to foster their students' creativity and critical thinking. At a minimum, teams were required to introduce the project materials, objectives and suggested pedagogical approaches to teachers by organising a one-day induction training session at the beginning of the project.