Spread the idea and gain consensus
Have them work through the same process of working through suggestions that students could make at a classroom or school yard. As an exercise, have them think about their own requests, assess them against the restrictions of “too much time, too much money or negatively impacts on someone else”. You will find it actually forms quite a robust test.
Implementing the '“Yes” is the default policy' at TC did not require extra funding or building. Teachers were enthusiastic because they went from teaching students who had no say in their learning where many students didn’t want to be there, to a class comprising significant numbers of self-empowered learners. Teachers themselves also felt more empowered because they were also permitted to “Take Control” of their learning and have their suggestions objectively assessed against the same standards.